Wireless communication enhancements for transparent and boundary clocks

ABSTRACT

Methods, systems, and devices for wireless communications are described. In an example ingress point of a wireless communication network, a method includes receiving a first ethernet frame comprising a precision time protocol (PTP) message at a first node and determining an ingress time for the PTP message, generating a packet data unit (PDU) for transmission to a second node of the wireless communication network based at least in part on the first ethernet frame by overwriting a field in the PTP message with a value corresponding to the ingress time, and sending the PDU to the second node. An egress point method may include receiving a PDU comprising a PTP message, determining an ingress time from a field in the PTP message overwritten with a value corresponding to the ingress time, and determining an adjustment for a timing parameter based at least in part on the ingress time.

CROSS REFERENCE

The present application for patent claims the benefit of U.S.Provisional Patent Application No. 62/791,704 by Joseph et al., entitled“WIRELESS COMMUNICATION ENHANCEMENTS FOR TRANSPARENT AND BOUNDARYCLOCKS,” filed Jan. 11, 2019, assigned to the assignee hereof, andexpressly incorporated herein.

BACKGROUND

The following relates generally to wireless communications, and morespecifically to wireless communication enhancements for transparent andboundary clocks.

Wireless communication networks are widely deployed to provide varioustypes of communication content such as voice, video, packet data,messaging, broadcast, and so on. These systems may be capable ofsupporting communication with multiple users by sharing the availablesystem resources (e.g., time, frequency, and power). Examples of suchmultiple-access systems include fourth generation (4G) systems such asLong Term Evolution (LTE) systems, LTE-Advanced (LTE-A) systems, orLTE-A Pro systems, and fifth generation (5G) systems which may bereferred to as New Radio (NR) systems. These systems may employtechnologies such as code division multiple access (CDMA), time divisionmultiple access (TDMA), frequency division multiple access (FDMA),orthogonal frequency division multiple access (OFDMA), or discreteFourier transform spread orthogonal frequency division multiplexing(DFT-S-OFDM). A wireless multiple-access communications system mayinclude a number of base stations or network access nodes, eachsimultaneously supporting communication for multiple communicationdevices, which may be otherwise known as user equipment (UE).

Some networks or systems may employ time-sensitive operations. Forexample, Industrial Internet of Things (IIoT) networks may implementcomplex interactions between different machines (e.g., robots,conveyors, etc.) for manufacturing. Time synchronization techniques maybe used to synchronize clocks among components of the network and toconvey ingress times for received packets. Some networks may usemessages, such as Precision Time Protocol (PTP) messages, for informingnodes of the network of information related to timing. However,employing a wireless communication network in these types of systems fordistributing communications between network nodes may provide challengesin maintaining timing synchronization.

SUMMARY

The described techniques relate to improved methods, systems, devices,and apparatuses that support wireless communication enhancements fortransparent and boundary clocks. Generally, the described techniquesprovide for improvements to time-sensitive network operations. Timesynchronization techniques may be used to synchronize clocks amongvarious components of the network and to convey ingress times for whenpackets and frames are received. Some networks may use messages, such asPrecision Time Protocol (PTP) messages, for informing network nodes ofinformation related to timing. Different techniques may be used for whena network node functions according to different timing mechanisms (e.g.,a transparent clock or a boundary clock). Link delays may be signaledand corrected for where relevant. A node may be informed of when to lookfor PTP messages. Techniques described herein further include selectingtiming domains and providing indications to nodes of the selected timingdomains.

A method at a first node of a wireless communication network isdescribed. The method may include receiving a first ethernet frameincluding a PTP message, determining an ingress time for the PTP messagereceived at the first node, generating a PDU for transmission to asecond node of the wireless communication network based on the firstethernet frame by overwriting a field in the PTP message with a valuecorresponding to the ingress time for the PTP message, and sending thePDU to the second node.

An apparatus is described. The apparatus may include a processor, memoryin electronic communication with the processor, and instructions storedin the memory. The instructions may be executable by the processor tocause the apparatus to receive a first ethernet frame including a PTPmessage, determine an ingress time for the PTP message received at thefirst node, generate a PDU for transmission to a second node of thewireless communication network based on the first ethernet frame byoverwriting a field in the PTP message with a value corresponding to theingress time for the PTP message, and send the PDU to the second node.

Another apparatus is described. The apparatus may include means forreceiving a first ethernet frame including a PTP message, means fordetermining an ingress time for the PTP message received at the firstnode, generating a PDU for transmission to a second node of the wirelesscommunication network based on the first ethernet frame by overwriting afield in the PTP message with a value corresponding to the ingress timefor the PTP message, and means for sending the PDU to the second node.

A non-transitory computer-readable medium storing code is described. Thecode may include instructions executable by a processor to receive afirst ethernet frame including a PTP message, determine an ingress timefor the PTP message received at the first node, generate a PDU fortransmission to a second node of the wireless communication networkbased on the first ethernet frame by overwriting a field in the PTPmessage with a value corresponding to the ingress time for the PTPmessage, and send the PDU to the second node.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, the PTP message may be a Syncmessage or a Follow_Up message. In an example where the PTP message is aSync message, in the method, apparatuses, and non-transitorycomputer-readable medium, generating the PDU for transmission mayfurther include operations, features, means, or instructions foroverwriting a timestamp field of the Sync PTP message with the valuecorresponding to the ingress time. In other examples, generating the PDUfor transmission may further include operations, features, means, orinstructions for overwriting a field of a header of the Sync PTP messagewith the value corresponding to the ingress time.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, generating the PDU fortransmission may further include operations, features, means, orinstructions for overwriting a type linked value (TLV) of the PTPmessage with the value corresponding to the ingress time.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, generating the PDU mayfurther include operations, features, means, or instructions foradjusting the ingress time for the PTP message to account for a linkdelay associated with the PTP message.

Some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein may further includeoperations, features, means, or instructions for providing an indicationto the second node that an associated PDU session may carry PTPmessages.

Some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein may further includeoperations, features, means, or instructions for signaling that thefirst node can filter sync messages associated with the PTP message.

The first node may be one of a user equipment (UE), a user planefunction (UPF), or an adaptor connected to a UE or UPF. In someexamples, generating the PDU further includes adjusting the ingress timefor the PTP message to account for a link delay associated with the PTPmessage.

Another method at a first node of a wireless communication network isdescribed. The method may include receiving, from a second node of thewireless communication network, a PDU including a PTP message,determining an ingress time for the PTP message for the wirelesscommunication network from a field in the PTP message overwritten with avalue corresponding to the ingress time for the PTP message, anddetermining an adjustment for a timing parameter associated with the PTPmessage based on the ingress time.

An apparatus is described. The apparatus may include a processor, memoryin electronic communication with the processor, and instructions storedin the memory. The instructions may be executable by the processor tocause the apparatus to receive, from a second node of the wirelesscommunication network, a PDU including a PTP message, determine aningress time for the PTP message for the wireless communication networkfrom a field in the PTP message overwritten with a value correspondingto the ingress time for the PTP message, and determine an adjustment fora timing parameter associated with the PTP message based on the ingresstime.

Another apparatus is described. The apparatus may include means forreceiving, from a second node of the wireless communication network, aPDU including a PTP message, means for determining an ingress time forthe PTP message for the wireless communication network from a field inthe PTP message overwritten with a value corresponding to the ingresstime for the PTP message, and means for determining an adjustment for atiming parameter associated with the PTP message based on the ingresstime.

A non-transitory computer-readable medium storing code is described. Thecode may include instructions executable by a processor to receive, froma second node of the wireless communication network, a PDU including aPTP message, determine an ingress time for the PTP message for thewireless communication network from a field in the PTP messageoverwritten with a value corresponding to the ingress time for the PTPmessage, and determine an adjustment for a timing parameter associatedwith the PTP message based on the ingress time.

Some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein may further includeoperations, features, means, or instructions for determining an egresstime for a second ethernet frame including the PTP message from thefirst node, determining a residence time correction for the ethernetframe including the PTP message time by subtracting the ingress timefrom the egress time, and transmitting the second ethernet frame to atime sensitive network, where the second ethernet frame includes amodified version of the PTP message.

Some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein may further includeoperations, features, means, or instructions for adjusting the modifiedversion of the PTP message by setting the overwritten field in the PTPmessage to a configured value.

Some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein may further includeoperations, features, means, or instructions for transmitting the secondethernet frame to a time sensitive network, where a correction field ofthe modified version of the PTP message may be adjusted by the residencetime correction.

The first node may be one of a UE, UPF, or an adaptor connected to a UEor UPF.

Some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein may further includeoperations, features, means, or instructions for receiving an indicationthat a PDU session associated with the PTP message carries PTP messages.

A method at a first node of a wireless communication network isdescribed. The method may include receiving a frame including a PTPmessage. The method may also include transmitting, to a second node ofthe wireless communication network, a session connectivity messageassociated with a PDU session for conveying the frame, the sessionconnectivity message including an indicator that the PDU sessionsupports PTP messages. The method may also include sending, to thesecond node, a PDU including the PTP message.

An apparatus is described. The apparatus may include a processor, memoryin electronic communication with the processor, and instructions storedin the memory. The instructions may be executable by the processor tocause the apparatus to receive a frame including a PTP message. Theinstructions may be executable by the processor to further cause theapparatus to transmit, to a second node of the wireless communicationnetwork, a session connectivity message associated with a PDU sessionfor conveying the frame, the session connectivity message including anindicator that the PDU session supports PTP messages and send, to thesecond node, a PDU including the PTP message.

Another apparatus is described. The apparatus may include means forreceiving a frame including a PTP message, means for transmitting, to asecond node of the wireless communication network, a sessionconnectivity message associated with a PDU session for conveying theframe, the session connectivity message including an indicator that thePDU session supports PTP messages, and means for sending, to the secondnode, a PDU including the PTP message.

A non-transitory computer-readable medium storing code is described. Thecode may include instructions executable by a processor to receive aframe including a PTP message, transmit, to a second node of thewireless communication network, a session connectivity messageassociated with a PDU session for conveying the frame, the sessionconnectivity message including an indicator that the PDU sessionsupports PTP messages, and send, to the second node, a PDU including thePTP message.

Some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein may further includeoperations, features, means, or instructions for determining an ingresstime for the PTP message, and generating the PDU by inserting a valuecorresponding to the ingress time for the PTP message.

Another method at a first node of a wireless communication network isdescribed. The method may include receiving, from a second node of thewireless communication network, a session connectivity messageassociated with a PDU session, the session connectivity messageincluding an indicator that the PDU session supports PTP messages,monitoring one or more PDUs received from the second node for PTPmessages based on the indicator that the PDU session supports PTPmessages, and identifying a PTP message in a PDU of the one or more PDUsbased on the monitoring.

An apparatus is described. The apparatus may include a processor, memoryin electronic communication with the processor, and instructions storedin the memory. The instructions may be executable by the processor tocause the apparatus to receive, from a second node of the wirelesscommunication network, a session connectivity message associated with aPDU session, the session connectivity message including an indicatorthat the PDU session supports PTP messages, monitor one or more PDUsreceived from the second node for PTP messages based on the indicatorthat the PDU session supports PTP messages, and identify a PTP messagein a PDU of the one or more PDUs based on the monitoring.

Another apparatus is described. The apparatus may include means forreceiving, from a second node of the wireless communication network, asession connectivity message associated with a PDU session, the sessionconnectivity message including an indicator that the PDU sessionsupports PTP messages, means for monitoring one or more PDUs receivedfrom the second node for PTP messages based on the indicator that thePDU session supports PTP messages, and means for identifying a PTPmessage in a PDU of the one or more PDUs based on the monitoring.

A non-transitory computer-readable medium storing code is described. Thecode may include instructions executable by a processor to receive, froma second node of the wireless communication network, a sessionconnectivity message associated with a PDU session, the sessionconnectivity message including an indicator that the PDU sessionsupports PTP messages, monitor one or more PDUs received from the secondnode for PTP messages based on the indicator that the PDU sessionsupports PTP messages, and identify a PTP message in a PDU of the one ormore PDUs based on the monitoring.

Some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein may further includeoperations, features, means, or instructions for determining an ingresstime for the PTP message for the wireless communication network from avalue corresponding to the ingress time for the PTP message inserted inthe PDU, and adjusting a timing parameter associated with the PTPmessage based on the ingress time.

Another method at a first node of a wireless communication network isdescribed. The method may include receiving, at a first node of awireless communication network, a first ethernet frame including a firstPTP message, determining an ingress time for the first PTP messagereceived at the first node, receiving a second ethernet frame includinga second PTP message associated with the first PTP message, generating aPDU for transmission to a second node of the wireless communicationnetwork based on the second ethernet frame, the PDU including a valuecorresponding to the ingress time for the first PTP message, andtransmitting the PDU to the second node.

An apparatus is described. The apparatus may include a processor, memoryin electronic communication with the processor, and instructions storedin the memory. The instructions may be executable by the processor tocause the apparatus to receive, at a first node of a wirelesscommunication network, a first ethernet frame including a first PTPmessage, determine an ingress time for the first PTP message received atthe first node, receive a second ethernet frame including a second PTPmessage associated with the first PTP message, generate a PDU fortransmission to a second node of the wireless communication networkbased on the second ethernet frame, the PDU including a valuecorresponding to the ingress time for the first PTP message, andtransmit the PDU to the second node.

Another apparatus is described. The apparatus may include means forreceiving, at a first node of a wireless communication network, a firstethernet frame including a first PTP message, means for determining aningress time for the first PTP message received at the first node, andmeans for receiving a second ethernet frame including a second PTPmessage associated with the first PTP message. The apparatus may alsoinclude means for generating a PDU for transmission to a second node ofthe wireless communication network based on the second ethernet frame,the PDU including a value corresponding to the ingress time for thefirst PTP message and means for transmitting the PDU to the second node.

A non-transitory computer-readable medium storing code is described. Thecode may include instructions executable by a processor to receive, at afirst node of a wireless communication network, a first ethernet frameincluding a first PTP message, determine an ingress time for the firstPTP message received at the first node, receive a second ethernet frameincluding a second PTP message associated with the first PTP message,generate a PDU for transmission to a second node of the wirelesscommunication network based on the second ethernet frame, the PDUincluding a value corresponding to the ingress time for the first PTPmessage, and transmit the PDU to the second node.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, generating the PDU fortransmission may include operations, features, means, or instructionsfor appending the value corresponding to the ingress time for the firstPTP message to the second ethernet frame in the PDU.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, generating the PDU fortransmission may further include operations, features, means, orinstructions for modifying the second ethernet frame by overwriting atimestamp field of the second PTP message with the value correspondingto the ingress time.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, generating the PDU fortransmission may further include operations, features, means, orinstructions for modifying the second ethernet frame by overwriting afield of a header of the second PTP message with the value correspondingto the ingress time.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, where generating the PDU mayfurther include operations, features, means, or instructions formodifying the second ethernet frame by overwriting a TLV of the secondPTP message with the value corresponding to the ingress time.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, generating the PDU mayfurther include operations, features, means, or instructions foradjusting the ingress time for the PTP message to account for a linkdelay associated with the PTP message.

Some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein may further includeoperations, features, means, or instructions for providing an indicationto the second node that an associated PDU session may carry PTPmessages.

Some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein may further includeoperations, features, means, or instructions for suppressingtransmission of the first PTP message to the second node.

Some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein may further includeoperations, features, means, or instructions for receiving an indicatorof support of the second node for suppressing transmission of the firstPTP message to the second node. In some examples, the indicator isassociated with a PDU session associated with the first and second PTPmessages. The indicator may be associated with the PDU.

Some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein may further includeoperations, features, means, or instructions for signaling that thefirst node can filter sync messages associated with the PTP message.

A method at a first node of a wireless communication network isdescribed. The method may include receiving, from a second node of thewireless communication network, a PDU associated with first and secondethernet frames received at the second node, the first ethernet frameincluding a first PTP message, and the second ethernet frame including asecond PTP message, determining an ingress time for the first PTPmessage received at the second node based on the PDU, and determining anadjustment for a timing parameter of the second PTP message based on theingress time.

An apparatus is described. The apparatus may include a processor, memoryin electronic communication with the processor, and instructions storedin the memory. The instructions may be executable by the processor tocause the apparatus to receive, from a second node of the wirelesscommunication network, a PDU associated with first and second ethernetframes received at the second node, the first ethernet frame including afirst PTP message, and the second ethernet frame including a second PTPmessage, determine an ingress time for the first PTP message received atthe second node based on the PDU, and determine an adjustment for atiming parameter of the second PTP message based on the ingress time.

Another apparatus is described. The apparatus may include means forreceiving, from a second node of the wireless communication network, aPDU associated with first and second ethernet frames received at thesecond node, the first ethernet frame including a first PTP message, andthe second ethernet frame including a second PTP message. The apparatusmay also include means for determining an ingress time for the first PTPmessage received at the second node based on the PDU means for anddetermining an adjustment for a timing parameter of the second PTPmessage based on the ingress time.

A non-transitory computer-readable medium storing code is described. Thecode may include instructions executable by a processor to receive, froma second node of the wireless communication network, a PDU associatedwith first and second ethernet frames received at the second node, thefirst ethernet frame including a first PTP message, and the secondethernet frame including a second PTP message, determine an ingress timefor the first PTP message received at the second node based on the PDU,and determine an adjustment for a timing parameter of the second PTPmessage based on the ingress time.

Some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein may further includeoperations, features, means, or instructions for determining an egresstime for a third ethernet frame including a modified version of thefirst PTP message, and determining a residence time correction for themodified version of the first PTP message time by subtracting theingress time from the egress time.

Some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein may further includeoperations, features, means, or instructions for transmitting the thirdethernet frame and a fourth ethernet frame including a modified versionof the second PTP message that identifies an adjustment to a timesensitive network, where a correction field of the modified version ofthe second PTP message may be modified using the residence timecorrection.

In some examples, determining the ingress time comprises one ofidentifying a value corresponding to the ingress time for the first PTPmessage from an overwritten field of the second PTP message oridentifying one or more octets corresponding to the ingress time in thePDU.

Some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein may further includeoperations, features, means, or instructions for receiving an indicationthat a PDU session associated with the first and second PTP messagessupports PTP messages.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein, determining the adjustmentmay further include operations, features, means, or instructions foradjusting the modified version of the second PTP message by setting theoverwritten field in the PTP message to a configured value.

Another method at a first node of a wireless communication network isdescribed. The method may include receiving, from a time sensitivenetwork, an ethernet frame including a PTP message, determining a linkdelay time for the PTP message between transmission from the timesensitive network and reception by the first node, generating a PDU fortransmission to a second node of the wireless communication networkbased on adjusting a field of the PTP message according to a link delay,and transmitting the PDU to the second node.

An apparatus is described. The apparatus may include a processor, memoryin electronic communication with the processor, and instructions storedin the memory. The instructions may be executable by the processor tocause the apparatus to receive, from a time sensitive network, anethernet frame including a PTP message, determine a link delay time forthe PTP message between transmission from the time sensitive network andreception by the first node, generate a PDU for transmission to a secondnode of the wireless communication network based on adjusting a field ofthe PTP message according to a link delay, and transmit the PDU to thesecond node.

Another apparatus is described. The apparatus may include means forreceiving, from a time sensitive network, an ethernet frame including aPTP message, means for determining a link delay time for the PTP messagebetween transmission from the time sensitive network and reception bythe first node, means for generating a PDU for transmission to a secondnode of the wireless communication network based on adjusting a field ofthe PTP message according to a link delay, and means for transmittingthe PDU to the second node.

A non-transitory computer-readable medium storing code is described. Thecode may include instructions executable by a processor to receive, froma time sensitive network, an ethernet frame including a PTP message,determine a link delay time for the PTP message between transmissionfrom the time sensitive network and reception by the first node,generate a PDU for transmission to a second node of the wirelesscommunication network based on adjusting a field of the PTP messageaccording to a link delay, and transmit the PDU to the second node.

In some examples, the PTP message is one of a Sync message or aFollow_Up message. In some examples, the first node is one of a UE, aUPF, or an adaptor connected to a UE or UPF.

Another method at a first node of a wireless communication network isdescribed. The method may include receiving a PTP message, identifyingone or more relevant timing domains for the wireless communicationnetwork based on the PTP message, and maintaining a boundary clock foreach of the one or more timing domains.

An apparatus is described. The apparatus may include a processor, memoryin electronic communication with the processor, and instructions storedin the memory. The instructions may be executable by the processor tocause the apparatus to receive a PTP message, identify one or morerelevant timing domains for the wireless communication network based onthe PTP message, and maintain a boundary clock for each of the one ormore timing domains.

Another apparatus is described. The apparatus may include means forreceiving a PTP message, means for identifying one or more relevanttiming domains for the wireless communication network based on the PTPmessage, and means for maintaining a boundary clock for each of the oneor more timing domains.

A non-transitory computer-readable medium storing code is described. Thecode may include instructions executable by a processor to receive a PTPmessage, identify one or more relevant timing domains for the wirelesscommunication network based on the PTP message, and maintain a boundaryclock for each of the one or more timing domains.

Some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein may further includeoperations, features, means, or instructions for identifying a networktag in a frame associated with the PTP message, where identifying theone or more timing domains may be further based on the network tag.

Some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein may further includeoperations, features, means, or instructions for receiving, from thesecond node, timing information for the one or more timing domains.

Some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein may further includeoperations, features, means, or instructions for transmitting, to asecond node of the wireless communication network, an indicator of theone or more timing domains supported by the first node.

In some examples, the timing information is received via broadcastsignaling of a serving cell or via a unicast message from the servingcell.

Some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein may further includeoperations, features, means, or instructions for sending a second PTPmessage to a node of a time sensitive network associated with a timingdomain of the one or more timing domains based on the respectiveboundary clock associated with the timing domain. In some examples,sending the second PTP message comprises sending an ethernet framecomprising a network tag associated with the timing domain.

Some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein may further includeoperations, features, means, or instructions for removing a timingdomain from the one or more timing domains based on the PTP message.

A method at a first node of a wireless communication network isdescribed. The method may include receiving, from one or more UEs servedby the first node, an indicator of one or more timing domains to besupported by the one or more UEs and transmitting, for each timingdomain of the one or more timing domains, an identifier of the timingdomain and timing information associated with the timing domain.

An apparatus is described. The apparatus may include a processor, memoryin electronic communication with the processor, and instructions storedin the memory. The instructions may be executable by the processor tocause the apparatus to receive, from one or more UEs served by the firstnode, an indicator of one or more timing domains to be supported by theone or more UEs and transmit, for each timing domain of the one or moretiming domains, an identifier of the timing domain and timinginformation associated with the timing domain.

Another apparatus is described. The apparatus may include means forreceiving, from one or more UEs served by the first node, an indicatorof one or more timing domains to be supported by the one or more UEs andmeans for transmitting, for each timing domain of the one or more timingdomains, an identifier of the timing domain and timing informationassociated with the timing domain.

A non-transitory computer-readable medium storing code is described. Thecode may include instructions executable by a processor to receive, fromone or more UEs served by the first node, an indicator of one or moretiming domains to be supported by the one or more UEs and transmit, foreach timing domain of the one or more timing domains, an identifier ofthe timing domain and timing information associated with the timingdomain.

Some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein may further includeoperations, features, means, or instructions for identifying a networktag associated with the timing domain in a frame associated with the PTPmessage, where identifying the one or more timing domains based on thenetwork tag.

Some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein may further includeoperations, features, means, or instructions for transmitting, to asecond node of the wireless communication network, an indicator of thenetwork tag with the identifier of the timing domain.

Some examples may include that the timing information is transmitted viabroadcast signaling or via a unicast message to the one or more UEs.

Some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein may further includeoperations, features, means, or instructions for removing a timingdomain from the one or more timing domains based on the PTP message.

A method at a first node of a wireless communication network isdescribed. The method may include receiving, from a second node of thewireless communication network, an indicator of one or more supportedtiming domains.

An apparatus is described. The apparatus may include a processor, memoryin electronic communication with the processor, and instructions storedin the memory. The instructions may be executable by the processor tocause the apparatus to receive, from a second node of the wirelesscommunication network, an indicator of one or more supported timingdomains.

Another apparatus is described. The apparatus may include means forreceiving, from a second node of the wireless communication network, anindicator of one or more supported timing domains.

A non-transitory computer-readable medium storing code is described. Thecode may include instructions executable by a processor to receive, froma second node of the wireless communication network, an indicator of oneor more supported timing domains.

In some examples of the method, apparatuses, and non-transitorycomputer-readable medium, the indicator of the one or more supportedtiming domains indicates support for the supported timing domain at thesecond node or at a third node.

Some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein may further includeoperations, features, means, or instructions for receiving a firstethernet frame including a PTP message, identifying a timing domainassociated with the PTP message, and sending a PDU to the third nodeincluding a modified version of the PTP message based on the timingdomain being one of the one or more timing domains.

Some examples of the method, apparatuses, and non-transitorycomputer-readable medium described herein may further includeoperations, features, means, or instructions for identifying a networktag in the ethernet frame, where identifying the timing domainassociated with the PTP message may be further based on the network tag.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates an example of a system for wireless communicationsthat supports wireless communication enhancements for transparent andboundary clocks in accordance with aspects of the present disclosure.

FIG. 2 illustrates an example of a communication system that supportswireless communication enhancements for transparent and boundary clocksin accordance with aspects of the present disclosure.

FIGS. 3A and 3B illustrate examples of a timing diagram for transparentclocks and boundary clocks in accordance with aspects of the presentdisclosure.

FIG. 4 illustrates an example of a communication system that supportswireless communication enhancements for transparent clocks in accordancewith aspects of the present disclosure.

FIGS. 5A and 5B illustrate examples of process flows that supportswireless communication enhancements for boundary clocks in accordancewith aspects of the present disclosure.

FIG. 6 illustrates an example of a communication system that supportswireless communication enhancements for transparent and boundary clocksin accordance with aspects of the present disclosure.

FIGS. 7 and 8 show block diagrams of devices that support wirelesscommunication enhancements for transparent and boundary clocks inaccordance with aspects of the present disclosure.

FIG. 9 shows a block diagram of a communications manager that supportswireless communication enhancements for transparent and boundary clocksin accordance with aspects of the present disclosure.

FIG. 10 shows a block diagram of a wireless device that supportswireless communication enhancements for transparent and boundary clocksin accordance with aspects of the present disclosure.

FIGS. 11 through 24 show flowcharts illustrating methods that supportwireless communication enhancements for transparent and boundary clocksin accordance with aspects of the present disclosure.

DETAILED DESCRIPTION

Some networks or systems may employ time-sensitive operations. Forexample, Industrial Internet of Things (IIoT) may implement complexinteractions between different machines (e.g., robots, conveyors, etc.)for manufacturing. Time synchronization techniques may be used tosynchronize clocks among components of the network and to convey ingresstimes for received packets. Some networks may use messages, such asPrecision Time Protocol (PTP) messages, for informing nodes of thenetwork about information related to timing. However, employing awireless communication network in these types of systems fordistributing communications between network nodes may provide challengesin maintaining timing synchronization. The present description providestechniques for a wireless communication system to support timesynchronization of components of a time-sensitive network connected viathe wireless communication system. Time synchronization can be used tomatch timing domains and reduce the amount of synchronization errorwithin a network.

A data packet or frame (e.g., an ethernet frame) may be received at anode of a wireless communication system. Reception of the frame may bereferred to as an ingress, and the time the frame is received may bereferred to as the ingress time. When the wireless communication systemthen sends a frame related to the received frame, the frame egressesfrom a node of the wireless communication system. In order to improvetiming synchronization, these ingress and egress times can be used tocorrect timing or identify timing domains.

Different techniques are presented for different configurations andoperations of the wireless communication system. For example, a wirelesscommunication system may operate as a transparent clock (e.g., anend-to-end transparent clock, a peer-to-peer transparent clock, etc.)for one or two-step time synchronization messages or as a boundaryclock. A wireless communication system that operates as a transparentclock performs a residence time correction for frames in order fornetworks communicating via the wireless communication system to achievemore accurate synchronization. A wireless communication system thatoperates as a boundary clock runs one or more master and slave clocks towhich clocks at the endpoints of a time sensitive network maysynchronize.

If the wireless communication system performs residence time correctionfor each PTP message that traverses the wireless communication system,it will determine the time spent by each PTP message in the transit.Time spent by a PTP message prior to egressing at an egress point can becomputed at the egress point if the ingress time is known at the egresspoint. For example, time spent prior to the egress point can be theegress time minus the ingress time. The time measured may be withrespect to a clock known at both the ingress point and the egress point.The ingress time of a PTP message may be determined based on an ingresstime of an ethernet frame containing the PTP message. The egress time ofa PTP message may be determined based on the egress time of an ethernetframe containing the PTP message. A determination of the ingress timemay use a timestamp of the ingress time (e.g., at the hardware or lowerlayers of wireless communication device) that was recorded prior to thedetermination. For example, the determination of the ingress time maytake place after the actual ingress of the packet. The determination ofthe egress time can use a timestamp of egress (e.g., at hardware orlower layers of wireless communication device) that was recorded priorto the determination (i.e., the determination may take place afteringress).

Some techniques described herein address compensation for a link delayby the wireless communication system. If a wireless communication systemacts as a peer-to-peer transparent clock system, performance may beenhanced by correcting for the delay (e.g., a link delay) of theincoming link. Techniques described herein provide field modificationassociated with timing in order to compensate for the link delay.

Other techniques address how to reduce processing overhead associatedwith a search for PTP messages. When a wireless communication systemacts as a transparent clock and UE is an egress point for PTP messages,the UE monitors each PDU carried over each PDU session for the PTPmessages, even when some sessions may not carry PTP messages. Techniquesdescribed herein provide for an indication that a PDU session may carryPTP messages. In some examples, the indication may be sent using aninformation element and may only be applicable for ethernet PDUsessions. In some examples, the UE or UPF may only look for PTP messagesin a PDU session that has been indicated to carry PTP messages.

Other techniques address how to reduce processing overhead associatedSync messages. When a wireless communication system acts as atransparent clock, Sync messages may be suppressed from the UE to a UPFor from the UPF to a UE as long the ingress time associated with theSync message can be signaled to a wireless communication system egresspoint. A PDU session carrying PTP messages may however carry all PTPmessages between a wireless communication system ingress point and a 5GSegress point, consuming resources on the backhaul, fronthaul, and radio.Techniques described herein provide for an indication that a UE/UPFacting as a wireless communication system ingress point (which can be aUE or UPF) can filter out Sync messages. In some examples, theindication may be sent using an optional IE and may only be applicablefor ethernet PDU sessions. In some examples, based on the signaling, theUE or UPF may act as an ingress point for PTP messages and may filterout Sync messages.

Other techniques described herein address how to determine timingdomains for wireless communication systems that act as boundary clocks.When a wireless communication system acts as a boundary clock for atiming domain, a UE associated with the wireless communication systemmay run a master clock based on timing information provided for thetiming domain. The master clock can be run in the UE or in anadaptor/translator connected to the UE. In some examples, an adaptorconnected to the UE also may be also used with a translator connected tothe UE. Similarly, an adaptor connected to the UPF also may be also usedwith a translator connected to the UPF. An adaptor or translatorconnected to the UE or UPF may behave as a TSN translator, such as thatdiscussed in 3GPP TR 23.734 v1.0.0. A UE may support more than onetiming domain. For example, this can be achieved by broadcasting timinginformation associated with the domains via a system information block(SIB). Techniques described herein provide for a UE to identify relevanttiming domains by tracking timing domain information in received PTPmessages and optionally tracking corresponding virtual local areanetwork (VLAN) tags associated with Ethernet packets containing the PTPmessages.

Aspects of the disclosure are initially described in the context of awireless communication network. Figures are presented which illustrateexamples related to a structure of wireless communication system,one-step and two-step transparent clock messages, clocks and timingdomains of a 5GS network, and a process flow regarding timesynchronization in a wireless communication system. Aspects of thedisclosure are further illustrated by and described with reference toapparatus diagrams, system diagrams, and flowcharts that relate towireless communication system enhancements for transparent and boundaryclocks.

FIG. 1 illustrates an example of a wireless communication network 100that supports wireless communication system enhancements for transparentand boundary clocks in accordance with aspects of the presentdisclosure. The wireless communication system 100 includes base stations105, UEs 115, and a core network 130. In some examples, the wirelesscommunication network 100 may be a Long Term Evolution (LTE) network, anLTE-Advanced (LTE-A) network, an LTE-A Pro network, or a New Radio (NR)network. In some cases, wireless communication network 100 may supportenhanced broadband communications, ultra-reliable (e.g., missioncritical) communications, low latency communications, or communicationswith low-cost and low-complexity devices.

Base stations 105 may wirelessly communicate with UEs 115 via one ormore base station antennas. Base stations 105 described herein mayinclude or may be referred to by those skilled in the art as a basetransceiver station, a radio base station, an access point, a radiotransceiver, a NodeB, an eNodeB (eNB), a next-generation NodeB (whichmay be referred to as a gNB), a Home NodeB, a Home eNodeB, or some othersuitable terminology. Wireless communication network 100 may includebase stations 105 of different types (e.g., macro or small cell basestations). The UEs 115 described herein may be able to communicate withvarious types of base stations 105 and network equipment including macroeNBs, small cell eNBs, gNBs, relay base stations, and the like.

Each base station 105 may be associated with a particular geographiccoverage area 110 in which communications with various UEs 115 issupported. Each base station 105 may provide communication coverage fora respective geographic coverage area 110 via communication links 125,and communication links 125 between a base station 105 and a UE 115 mayutilize one or more carriers. Communication links 125 shown in wirelesscommunication network 100 may include uplink transmissions from a UE 115to a base station 105, or downlink transmissions from a base station 105to a UE 115. Downlink transmissions may also be called forward linktransmissions while uplink transmissions may also be called reverse linktransmissions.

The geographic coverage area 110 for a base station 105 may be dividedinto sectors making up a portion of the geographic coverage area 110,and each sector may be associated with a cell. For example, each basestation 105 may provide communication coverage for a macro cell, a smallcell, a hot spot, or other types of cells, or various combinationsthereof. In some examples, a base station 105 may be movable andtherefore provide communication coverage for a moving geographiccoverage area 110. In some examples, different geographic coverage areas110 associated with different technologies may overlap. Overlappinggeographic coverage areas 110 associated with different technologies maybe supported by the same base station 105 or by different base stations105. The wireless communication network 100 may include, for example, aheterogeneous LTE/LTE-A/LTE-A Pro or NR network in which different typesof base stations 105 provide coverage for various geographic coverageareas 110.

The term “cell” refers to a logical communication entity used forcommunication with a base station 105 (e.g., over a carrier), and may beassociated with an identifier for distinguishing neighboring cells(e.g., a physical cell identifier (PCID), a virtual cell identifier(VCID)) operating via the same or a different carrier. In some examples,a carrier may support multiple cells, and different cells may beconfigured according to different protocol types (e.g., machine-typecommunication (MTC), narrowband Internet-of-Things (NB-IoT), enhancedmobile broadband (eMBB), or others) that may provide access fordifferent types of devices. In some cases, the term “cell” may refer toa portion of a geographic coverage area 110 (e.g., a sector) over whichthe logical entity operates.

UEs 115 may be dispersed throughout the wireless communication network100, and each UE 115 may be stationary or mobile. A UE 115 may also bereferred to as a mobile device, a wireless device, a remote device, ahandheld device, or a subscriber device, or some other suitableterminology, where the “device” may also be referred to as a unit, astation, a terminal, or a client. A UE 115 may also be a personalelectronic device such as a cellular phone, a personal digital assistant(PDA), a tablet computer, a laptop computer, or a personal computer. Insome examples, a UE 115 may also refer to a wireless local loop (WLL)station, an Internet of Things (IoT) device, an Internet of Everything(IoE) device, or an MTC device, or the like, which may be implemented invarious articles such as appliances, vehicles, meters, or the like.

Some UEs 115, such as MTC or IoT devices, may be low cost or lowcomplexity devices, and may provide for automated communication betweenmachines (e.g., via Machine-to-Machine (M2M) communication). M2Mcommunication or MTC may refer to data communication technologies thatallow devices to communicate with one another or a base station 105without human intervention. In some examples, M2M communication or MTCmay include communications from devices that integrate sensors or metersto measure or capture information and relay that information to acentral server or application program that can make use of theinformation or present the information to humans interacting with theprogram or application. Some UEs 115 may be designed to collectinformation or enable automated behavior of machines. Examples ofapplications for MTC devices include smart metering, inventorymonitoring, water level monitoring, equipment monitoring, healthcaremonitoring, wildlife monitoring, weather and geological eventmonitoring, fleet management and tracking, remote security sensing,physical access control, and transaction-based business charging.

Some UEs 115 may be configured to employ operating modes that reducepower consumption, such as half-duplex communications (e.g., a mode thatsupports one-way communication via transmission or reception, but nottransmission and reception simultaneously). In some examples half-duplexcommunications may be performed at a reduced peak rate. Other powerconservation techniques for UEs 115 include entering a power saving“deep sleep” mode when not engaging in active communications, oroperating over a limited bandwidth (e.g., according to narrowbandcommunications). In some cases, UEs 115 may be designed to supportcritical functions (e.g., mission critical functions), and a wirelesscommunication network 100 may be configured to provide ultra-reliablecommunications for these functions.

In some cases, a UE 115 may also be able to communicate directly withother UEs 115 (e.g., using a peer-to-peer (P2P) or device-to-device(D2D) protocol). One or more of a group of UEs 115 utilizing D2Dcommunications may be within the geographic coverage area 110 of a basestation 105. Other UEs 115 in such a group may be outside the geographiccoverage area 110 of a base station 105 or be otherwise unable toreceive transmissions from a base station 105. In some cases, groups ofUEs 115 communicating via D2D communications may utilize a one-to-many(1:M) system in which each UE 115 transmits to every other UE 115 in thegroup. In some cases, a base station 105 facilitates the scheduling ofresources for D2D communications. In other cases, D2D communications arecarried out between UEs 115 without the involvement of a base station105.

Base stations 105 may communicate with the core network 130 and with oneanother. For example, base stations 105 may interface with the corenetwork 130 through backhaul links 132 (e.g., via an S1, N2, N3, oranother interface). Base stations 105 may communicate with one anotherover backhaul links 134 (e.g., via an X2, Xn, or other interface) eitherdirectly (e.g., directly between base stations 105) or indirectly (e.g.,via core network 130).

The core network 130 may provide user authentication, accessauthorization, tracking, Internet Protocol (IP) connectivity, and otheraccess, routing, or mobility functions. The core network 130 may be anevolved packet core (EPC), which may include at least one mobilitymanagement entity (MME), at least one serving gateway (S-GW), and atleast one Packet Data Network (PDN) gateway (P-GW). The MME may managenon-access stratum (e.g., control plane) functions such as mobility,authentication, and bearer management for UEs 115 served by basestations 105 associated with the EPC. User IP packets may be transferredthrough the S-GW, which itself may be connected to the P-GW. The P-GWmay provide IP address allocation as well as other functions. The P-GWmay be connected to the network operators IP services. The operators IPservices may include access to the Internet, Intranet(s), an IPMultimedia Subsystem (IMS), or a Packet-Switched (PS) Streaming Service.

At least some of the network devices, such as a base station 105, mayinclude subcomponents such as an access network entity, which may be anexample of an access node controller (ANC). Each access network entitymay communicate with UEs 115 through a number of other access networktransmission entities, which may be referred to as a radio head, a smartradio head, or a transmission/reception point (TRP). In someconfigurations, various functions of each access network entity or basestation 105 may be distributed across various network devices (e.g.,radio heads and access network controllers) or consolidated into asingle network device (e.g., a base station 105).

Wireless communication network 100 may operate using one or morefrequency bands, typically in the range of 300 megahertz (MHz) to 300gigahertz (GHz). Generally, the region from 300 MHz to 3 GHz is known asthe ultra-high frequency (UHF) region or decimeter band, since thewavelengths range from approximately one decimeter to one meter inlength. UHF waves may be blocked or redirected by buildings andenvironmental features. However, the waves may penetrate structuressufficiently for a macro cell to provide service to UEs 115 locatedindoors. Transmission of UHF waves may be associated with smallerantennas and shorter range (e.g., less than 100 km) compared totransmission using the smaller frequencies and longer waves of the highfrequency (HF) or very high frequency (VHF) portion of the spectrumbelow 300 MHz.

Wireless communication network 100 may also operate in a super highfrequency (SHF) region using frequency bands from 3 GHz to 30 GHz, alsoknown as the centimeter band. The SHF region includes bands such as the5 GHz industrial, scientific, and medical (ISM) bands, which may be usedopportunistically by devices that may be capable of toleratinginterference from other users.

Wireless communication network 100 may also operate in an extremely highfrequency (EHF) region of the spectrum (e.g., from 30 GHz to 300 GHz),also known as the millimeter band. In some examples, wirelesscommunication network 100 may support millimeter wave (mmW)communications between UEs 115 and base stations 105, and EHF antennasof the respective devices may be even smaller and more closely spacedthan UHF antennas. In some cases, this may facilitate use of antennaarrays within a UE 115. However, the propagation of EHF transmissionsmay be subject to even greater atmospheric attenuation and shorter rangethan SHF or UHF transmissions. Techniques disclosed herein may beemployed across transmissions that use one or more different frequencyregions, and designated use of bands across these frequency regions maydiffer by country or regulating body.

In some cases, wireless communication network 100 may utilize bothlicensed and unlicensed radio frequency spectrum bands. For example,wireless communication network 100 may employ License Assisted Access(LAA), LTE-Unlicensed (LTE-U) radio access technology, or NR technologyin an unlicensed band such as the 5 GHz ISM band. When operating inunlicensed radio frequency spectrum bands, wireless devices such as basestations 105 and UEs 115 may employ listen-before-talk (LBT) proceduresto ensure a frequency channel is clear before transmitting data. In somecases, operations in unlicensed bands may be based on a carrieraggregation configuration in conjunction with component carriersoperating in a licensed band (e.g., LAA). Operations in unlicensedspectrum may include downlink transmissions, uplink transmissions,peer-to-peer transmissions, or a combination of these. Duplexing inunlicensed spectrum may be based on frequency division duplexing (FDD),time division duplexing (TDD), or a combination of both.

In some examples, base station 105 or UE 115 may be equipped withmultiple antennas, which may be used to employ techniques such astransmit diversity, receive diversity, multiple-input multiple-output(MIMO) communications, or beamforming. For example, wirelesscommunication network 100 may use a transmission scheme between atransmitting device (e.g., a base station 105) and a receiving device(e.g., a UE 115), where the transmitting device is equipped withmultiple antennas and the receiving device is equipped with one or moreantennas. MIMO communications may employ multipath signal propagation toincrease the spectral efficiency by transmitting or receiving multiplesignals via different spatial layers, which may be referred to asspatial multiplexing. The multiple signals may, for example, betransmitted by the transmitting device via different antennas ordifferent combinations of antennas. Likewise, the multiple signals maybe received by the receiving device via different antennas or differentcombinations of antennas. Each of the multiple signals may be referredto as a separate spatial stream and may carry bits associated with thesame data stream (e.g., the same codeword) or different data streams.Different spatial layers may be associated with different antenna portsused for channel measurement and reporting. MIMO techniques includesingle-user MIMO (SU-MIMO) where multiple spatial layers are transmittedto the same receiving device, and multiple-user MIMO (MU-MIMO) wheremultiple spatial layers are transmitted to multiple devices.

Beamforming, which may also be referred to as spatial filtering,directional transmission, or directional reception, is a signalprocessing technique that may be used at a transmitting device or areceiving device (e.g., a base station 105 or a UE 115) to shape orsteer an antenna beam (e.g., a transmit beam or receive beam) along aspatial path between the transmitting device and the receiving device.Beamforming may be achieved by combining the signals communicated viaantenna elements of an antenna array such that signals propagating atparticular orientations with respect to an antenna array experienceconstructive interference while others experience destructiveinterference. The adjustment of signals communicated via the antennaelements may include a transmitting device or a receiving deviceapplying certain amplitude and phase offsets to signals carried via eachof the antenna elements associated with the device. The adjustmentsassociated with each of the antenna elements may be defined by abeamforming weight set associated with a particular orientation (e.g.,with respect to the antenna array of the transmitting device orreceiving device, or with respect to some other orientation).

In one example, a base station 105 may use multiple antennas or antennaarrays to conduct beamforming operations for directional communicationswith a UE 115. For instance, some signals (e.g., synchronizationsignals, reference signals, beam selection signals, or other controlsignals) may be transmitted by a base station 105 multiple times indifferent directions, which may include a signal being transmittedaccording to different beamforming weight sets associated with differentdirections of transmission. Transmissions in different beam directionsmay be used to identify (e.g., by the base station 105 or a receivingdevice, such as a UE 115) a beam direction for subsequent transmissionand/or reception by the base station 105.

Some signals, such as data signals associated with a particularreceiving device, may be transmitted by a base station 105 in a singlebeam direction (e.g., a direction associated with the receiving device,such as a UE 115). In some examples, the beam direction associated withtransmissions along a single beam direction may be determined based atleast in in part on a signal that was transmitted in different beamdirections. For example, a UE 115 may receive one or more of the signalstransmitted by the base station 105 in different directions, and the UE115 may report to the base station 105 an indication of the signal itreceived with a highest signal quality, or an otherwise acceptablesignal quality. Although these techniques are described with referenceto signals transmitted in one or more directions by a base station 105,a UE 115 may employ similar techniques for transmitting signals multipletimes in different directions (e.g., for identifying a beam directionfor subsequent transmission or reception by the UE 115) or transmittinga signal in a single direction (e.g., for transmitting data to areceiving device).

A receiving device (e.g., a UE 115, which may be an example of a mmWreceiving device) may try multiple receive beams when receiving varioussignals from the base station 105, such as synchronization signals,reference signals, beam selection signals, or other control signals. Forexample, a receiving device may try multiple receive directions byreceiving via different antenna subarrays, by processing receivedsignals according to different antenna subarrays, by receiving accordingto different receive beamforming weight sets applied to signals receivedat a plurality of antenna elements of an antenna array, or by processingreceived signals according to different receive beamforming weight setsapplied to signals received at a plurality of antenna elements of anantenna array, any of which may be referred to as “listening” accordingto different receive beams or receive directions. In some examples areceiving device may use a single receive beam to receive along a singlebeam direction (e.g., when receiving a data signal). The single receivebeam may be aligned in a beam direction determined based at least inpart on listening according to different receive beam directions (e.g.,a beam direction determined to have a highest signal strength, highestsignal-to-noise ratio, or otherwise acceptable signal quality based atleast in part on listening according to multiple beam directions).

In some cases, the antennas of a base station 105 or UE 115 may belocated within one or more antenna arrays, which may support MIMOoperations, or transmit or receive beamforming. For example, one or morebase station antennas or antenna arrays may be co-located at an antennaassembly, such as an antenna tower. In some cases, antennas or antennaarrays associated with a base station 105 may be located in diversegeographic locations. A base station 105 may have an antenna array witha number of rows and columns of antenna ports that the base station 105may use to support beamforming of communications with a UE 115.Likewise, a UE 115 may have one or more antenna arrays that may supportvarious MIMO or beamforming operations.

In some cases, wireless communication network 100 may be a packet-basednetwork that operate according to a layered protocol stack. In the userplane, communications at the bearer or Packet Data Convergence Protocol(PDCP) layer may be IP-based. A Radio Link Control (RLC) layer mayperform packet segmentation and reassembly to communicate over logicalchannels. A Medium Access Control (MAC) layer may perform priorityhandling and multiplexing of logical channels into transport channels.The MAC layer may also use hybrid automatic repeat request (HARQ) toprovide retransmission at the MAC layer to improve link efficiency. Inthe control plane, the Radio Resource Control (RRC) protocol layer mayprovide establishment, configuration, and maintenance of an RRCconnection between a UE 115 and a base station 105 or core network 130supporting radio bearers for user plane data. At the Physical layer,transport channels may be mapped to physical channels.

In some cases, UEs 115 and base stations 105 may support retransmissionsof data to increase the likelihood that data is received successfully.HARQ feedback is one technique of increasing the likelihood that data isreceived correctly over a communication link 125. HARQ may include acombination of error detection (e.g., using a cyclic redundancy check(CRC)), forward error correction (FEC), and retransmission (e.g.,automatic repeat request (ARQ)). HARQ may improve throughput at the MAClayer in poor radio conditions (e.g., signal-to-noise conditions). Insome cases, a wireless device may support same-slot HARQ feedback, wherethe device may provide HARQ feedback in a specific slot for datareceived in a previous symbol in the slot. In other cases, the devicemay provide HARQ feedback in a subsequent slot, or according to someother time interval.

Time intervals in LTE or NR may be expressed in multiples of a basictime unit, which may, for example, refer to a sampling period ofT_(s)=1/30,720,000 seconds. Time intervals of a communications resourcemay be organized according to radio frames each having a duration of 10milliseconds (ms), where the frame period may be expressed asT_(f)=307,200 T_(s). The radio frames may be identified by a systemframe number (SFN) ranging from 0 to 1023. Each frame may include 10subframes numbered from 0 to 9, and each subframe may have a duration of1 ms. A subframe may be further divided into 2 slots each having aduration of 0.5 ms, and each slot may contain 6 or 7 modulation symbolperiods (e.g., depending on the length of the cyclic prefix prepended toeach symbol period). Excluding the cyclic prefix, each symbol period maycontain 2048 sampling periods. In some cases, a subframe may be thesmallest scheduling unit of the wireless communication network 100 andmay be referred to as a transmission time interval (TTI). In othercases, a smallest scheduling unit of the wireless communication network100 may be shorter than a subframe or may be dynamically selected (e.g.,in bursts of shortened TTIs (sTTIs) or in selected component carriersusing sTTIs).

In some wireless communication networks, a slot may further be dividedinto multiple mini-slots containing one or more symbols. In someinstances, a symbol of a mini-slot or a mini-slot may be the smallestunit of scheduling. Each symbol may vary in duration depending on thesubcarrier spacing or frequency band of operation, for example. Further,some wireless communication networks may implement slot aggregation inwhich multiple slots or mini-slots are aggregated together and used forcommunication between a UE 115 and a base station 105.

The term “carrier” refers to a set of radio frequency spectrum resourceshaving a defined physical layer structure for supporting communicationsover a communication link 125. For example, a carrier of a communicationlink 125 may include a portion of a radio frequency spectrum band thatis operated according to physical layer channels for a given radioaccess technology. Each physical layer channel may carry user data,control information, or other signaling. A carrier may be associatedwith a pre-defined frequency channel (e.g., an evolved universal mobiletelecommunication system terrestrial radio access (E-UTRA) absoluteradio frequency channel number (EARFCN)) and may be positioned accordingto a channel raster for discovery by UEs 115. Carriers may be downlinkor uplink (e.g., in an FDD mode), or be configured to carry downlink anduplink communications (e.g., in a TDD mode). In some examples, signalwaveforms transmitted over a carrier may be made up of multiplesub-carriers (e.g., using multi-carrier modulation (MCM) techniques suchas orthogonal frequency division multiplexing (OFDM) or discrete Fouriertransform spread OFDM (DFT-S-OFDM)).

The organizational structure of the carriers may be different fordifferent radio access technologies (e.g., LTE, LTE-A, LTE-A Pro, NR).For example, communications over a carrier may be organized according toTTIs or slots, each of which may include user data as well as controlinformation or signaling to support decoding the user data. A carriermay also include dedicated acquisition signaling (e.g., synchronizationsignals or system information, etc.) and control signaling thatcoordinates operation for the carrier. In some examples (e.g., in acarrier aggregation configuration), a carrier may also have acquisitionsignaling or control signaling that coordinates operations for othercarriers.

Physical channels may be multiplexed on a carrier according to varioustechniques. A physical control channel and a physical data channel maybe multiplexed on a downlink carrier, for example, using time divisionmultiplexing (TDM) techniques, frequency division multiplexing (FDM)techniques, or hybrid TDM-FDM techniques. In some examples, controlinformation transmitted in a physical control channel may be distributedbetween different control regions in a cascaded manner (e.g., between acommon control region or common search space and one or more UE-specificcontrol regions or UE-specific search spaces).

A carrier may be associated with a particular bandwidth of the radiofrequency spectrum, and in some examples the carrier bandwidth may bereferred to as a “system bandwidth” of the carrier or the wirelesscommunication network 100. For example, the carrier bandwidth may be oneof a number of predetermined bandwidths for carriers of a particularradio access technology (e.g., 1.4, 3, 5, 10, 15, 20, 40, or 80 MHz). Insome examples, each served UE 115 may be configured for operating overportions or all of the carrier bandwidth. In other examples, some UEs115 may be configured for operation using a narrowband protocol typethat is associated with a predefined portion or range (e.g., set ofsubcarriers or RBs) within a carrier (e.g., “in-band” deployment of anarrowband protocol type).

In a system employing MCM techniques, a resource element may compriseone symbol period (e.g., a duration of one modulation symbol) and onesubcarrier, where the symbol period and subcarrier spacing are inverselyrelated. The number of bits carried by each resource element may dependon the modulation scheme (e.g., the order of the modulation scheme).Thus, the more resource elements that a UE 115 receives and the higherthe order of the modulation scheme, the higher the data rate may be forthe UE 115. In MIMO systems, a wireless communications resource mayrefer to a combination of a radio frequency spectrum resource, a timeresource, and a spatial resource (e.g., spatial layers), and the use ofmultiple spatial layers may further increase the data rate forcommunications with a UE 115.

Devices of the wireless communication network 100 (e.g., base stations105 or UEs 115) may have a hardware configuration that supportscommunications over a particular carrier bandwidth or may beconfigurable to support communications over one of a set of carrierbandwidths. In some examples, the wireless communication network 100 mayinclude base stations 105 and/or UEs 115 that support simultaneouscommunications via carriers associated with more than one differentcarrier bandwidth.

Wireless communication network 100 may support communication with a UE115 on multiple cells or carriers, a feature which may be referred to ascarrier aggregation or multi-carrier operation. A UE 115 may beconfigured with multiple downlink component carriers and one or moreuplink component carriers according to a carrier aggregationconfiguration. Carrier aggregation may be used with both FDD and TDDcomponent carriers.

In some cases, wireless communication network 100 may utilize enhancedcomponent carriers (eCCs). An eCC may be characterized by one or morefeatures including wider carrier or frequency channel bandwidth, shortersymbol duration, shorter TTI duration, or modified control channelconfiguration. In some cases, an eCC may be associated with a carrieraggregation configuration or a dual connectivity configuration (e.g.,when multiple serving cells have a suboptimal or non-ideal backhaullink). An eCC may also be configured for use in unlicensed spectrum orshared spectrum (e.g., where more than one operator is allowed to usethe spectrum). An eCC characterized by wide carrier bandwidth mayinclude one or more segments that may be utilized by UEs 115 that arenot capable of monitoring the whole carrier bandwidth or are otherwiseconfigured to use a limited carrier bandwidth (e.g., to conserve power).

In some cases, an eCC may utilize a different symbol duration than othercomponent carriers, which may include use of a reduced symbol durationas compared with symbol durations of the other component carriers. Ashorter symbol duration may be associated with increased spacing betweenadjacent subcarriers. A device, such as a UE 115 or base station 105,utilizing eCCs may transmit wideband signals (e.g., according tofrequency channel or carrier bandwidths of 20, 40, 60, 80 MHz, etc.) atreduced symbol durations (e.g., 16.67 microseconds). A TTI in eCC maycomprise one or multiple symbol periods. In some cases, the TTI duration(that is, the number of symbol periods in a TTI) may be variable.

Wireless communication network 100 may be an NR system that may utilizeany combination of licensed, shared, and unlicensed spectrum bands,among others. The flexibility of eCC symbol duration and subcarrierspacing may allow for the use of eCC across multiple spectrums. In someexamples, NR shared spectrum may increase spectrum utilization andspectral efficiency, specifically through dynamic vertical (e.g., acrossthe frequency domain) and horizontal (e.g., across the time domain)sharing of resources.

One or more UEs 115 may include a communications manager, which mayperform time synchronization for a wireless communication system asdescribed herein. For example, a UE 115 may receive a first ethernetframe including a PTP message, determine an ingress time for the PTPmessage received at UE 115, generate a PDU for transmission to a secondnode of the wireless communication network based on the first ethernetframe by overwriting a field in the PTP message with a valuecorresponding to the ingress time for the PTP message, and send the PDUto the second node.

FIG. 2 illustrates an example of a communication system 200 thatsupports wireless communication system enhancements for transparent andboundary clocks in accordance with aspects of the present disclosure. Insome examples, communication system 200 may implement aspects ofwireless communication network 100. Communication system 200 may includetwo time sensitive networks 205-a and 205-b (collectively referred to asTSNs 205), a wireless communication network 210, and an endpoint 215.Communication system 200 may include different numbers of TSNs 205 andendpoints 215. Traffic and timing information may be exchanged betweenthe different components of communication system 200.

In some examples, one or more of the TSNs 205 may be networks includingcomponents that have relatively high requirements for synchronization.For example, TSNs 205 may be IIoT networks which may coordinate manycomponents at once. For example, an IIoT network may coordinate theactions of multiple fast moving robotic arms operating on an assemblyline. The IIoTs may have a synchronization error requirement of, forexample, less than or equal to 1 microsecond (p). TSNs 205 may use timesynchronization techniques to meet these synchronization errorrequirements. Time synchronization can be used to match timing domainsand reduce the amount of synchronization error within a network. In someexamples, one or more of TSNs 205 may be wired or wireless networks.

Wireless communication network 210 may support time synchronizationtechniques. For example, wireless communication network 210 may supportfeatures of the TSNs 205, such as time synchronization. Asynchronization protocol may be used for time synchronization, forexample, PTP versions 1 or 2, gPTP, or those defined in IEEE 1588-2008,1588-2002, or 802.1AS. In other examples, other synchronizationprotocols may be used. Generally, messages associated with theseprotocols are referred to herein as PTP messages. In different examples,a different system, technique, or protocol may be used for timesynchronization in wireless communication network 210.

Wireless communication network 210 may include a number of components,some of all of which may be considered nodes in wireless communicationnetwork 210. In the example shown in FIG. 2, wireless communicationnetwork 210 may include two or more adaptors or translators 220-a and220-b (collectively referred to herein as adaptor/translator 220), oneor more user plane functions (UPFs) 225, one or more radio accessnetworks (RANs) 230, and one or more UEs 235. In some examples, wirelesscommunication network 210 includes an adaptor/translator 220 and a UE orUPF for each endpoint 215 in communication system 200.

In some examples, wireless communication network 210 may be a 5G NRsystem. A data packet or frame (e.g., an ethernet frame) may arrive(e.g., ingress) at wireless communication network 210. The data packetor frame ingresses at a node of wireless communication network 210 at aparticular time. That time may be referred to as an ingress time. Whenwireless communication network 210 sends a data packet or frame relatedto the received information outside of wireless communication network210, the data packet or frame egresses from a node of wirelesscommunication network 210. In order to improve time synchronization,these ingress and egress times can be used to support timesynchronization of components of a TSN that communicate via the wirelesscommunication network 210.

Techniques described herein provide ways to convey an ingress time for aPTP message received at an ingress point of wireless communicationnetwork 210 to an egress point to improve support of timesynchronization for components communicating via wireless communicationnetwork 210. An ingress point of wireless communication network 210 maybe an adaptor/translator 220 connected to a UE 235 or a UPF 225 or maybe part of a UE 235 or a UPF 225. Likewise, an egress point of wirelesscommunication network 210 may be another adaptor/translator 220connected to a different UE 235 or a UPF 225 or may be part of adifferent UE 235 or a UPF 225. Any component of wireless communicationnetwork 210 that may serve as an ingress point or an egress point may bereferred to herein as a node.

FIGS. 3A and 3B illustrate different types of time synchronizationoperations that can affect timing in a wireless communication network.FIG. 3A illustrates an example of a timing diagram 300 that supports aone-step synchronization message in accordance with aspects of thepresent disclosure. In some examples, wireless communication networks100 or 200 may implement aspects of the timing diagram 300. Timingdiagram 300 illustrates differences in timing regarding a sync message315 according to two different clocks.

Timing diagram 300 illustrates how a time indicated at a master clock305, which may be a master clock in a TSN such as a TSN 205, may beconveyed to a slave clock 310. In some examples, master clock 305corresponds to a first node of a TSN and slave clock 310 corresponds toa different node of the TSN. According to a method of synchronizationusing the one-step synchronization message, a Sync message 315 (e.g., adata packet or a frame) departs the first node at time t₁ (i.e., theegress time) according to master clock 305. In the one-step operation,hardware (e.g., a physical layer) will timestamp Sync message 315 toidentify t₁.

Slave clock 310, operating at a second node of the wirelesscommunication network, determines an ingress time t₂ corresponding towhen the second node received Sync message 315. Thus, when slave clock310 receives Sync message 315, the second node knows the current timeand the time that Sync message 315 was sent according to master clock305. Thus, slave clock 310 can update its clock if necessary tosynchronize with master clock 305 based on the one-step Sync message315. Some of the techniques described herein apply to networks that usethe one-step operation.

However, it may be difficult to include the egress timestamp in the sameSync message 315 that is being sent because the first node cannot alwaysprecisely determine when it will send Sync message 315. For example,Sync message 315 may be generated by a layer different (e.g., above) aphysical layer of a device, and may not precisely control the egresstime.

FIG. 3B illustrates an example of a timing diagram 350 that supports atwo-step synchronization message in accordance with aspects of thepresent disclosure. In some examples, wireless communication network mayimplement aspects of the timing diagram 350. Timing diagram 300illustrates differences in timing regarding a Sync message 315 accordingto two different clocks.

Timing diagram 350 illustrates how a time indicated at a master clock355 may correspond to a time according to a slave clock 360. The masterclock 355 may be a master clock in a TSN and the slave clock 360 may bea slave clock in the TSN.

According to the method of synchronizing using the two-stepsynchronization message, a Sync message 365 (e.g., a data packet or aframe) departs the first node at time t₁ (i.e., the egress time)according to master clock 355. In contrast with the one-step operation,the Sync message 365 does not carry a time stamp of the egress time.Instead, the two-step operation sends a Follow_Up message 370 after Syncmessage 365 is sent. Follow_Up message 370 identifies t₁, the time thatSync message 365 was sent. In some cases, a more accurate timestamp fort₁ can be sent to the second node than in the one-step method.

Slave clock 310, operating at a second node of the TSN, determines aningress time t₂ corresponding to when the second node received Syncmessage 365. The second node determines t₁ from the timestamp inFollow_Up message 370. Thus, slave clock 360 can update its clock ifnecessary to synchronize with master clock 355 based on the two-stepSync message 365 and Follow_Up message 370. Some of the techniquesdescribed herein apply to networks that use the two-step operation.

FIG. 4 illustrates an example of a communication system 400 thatsupports wireless communication system enhancements for transparentclocks in accordance with aspects of the present disclosure. In someexamples, communication system 400 may implement aspects of wirelesscommunication network 100 and 200. FIG. 4 illustrates an example where awireless communication network 410 of communication system 400 may actas a transparent clock.

Communication system 400 may be an example of communication system 100or 200 of FIGS. 1 and 2, respectively. Communication system 400 mayinclude a TSN 405, wireless communication network 410, one or more TSNbridges 420, and endpoints 415-a and 415-b (collectively referred toherein as endpoints 415). In other examples, other numbers of TSNs 405,wireless communication networks 410, TSN bridges 420, and endpoints 415may be part of communication system 400, which may be examples ofaspects of the respective components as described above with referenceto FIGS. 1 and 2. In some cases, TSN bridges 420 and endpoints 415 maybe considered to be part of TSN 405.

Different approaches for synchronization of components of TSN 405 suchas endpoints 415 via wireless communication network 410 may be used. Inthe example of FIG. 4, wireless communication network 410 acts as atransparent clock. TSN 405 is shown including two different timingdomains corresponding to master clock 1 430-a and master clock 2 430-b.A slave clock 1 440-a and a slave clock 2 440-b in endpoints 415 areslaves of the master clock 1 430-a and master clock 2 430-b,respectively. Wireless communication system 410 includes at least onenode 435 that performs residence time correction for PTP messages thattravel through wireless communication system 410. In the example of FIG.4, wireless communication system 410 includes two nodes 435-a and 435-b,which each may correspond to a UE, a UPF, or an adaptor/translatorconnected with or incorporated in a UE or UPF.

The wireless communication system 410 may carry synchronization messages(e.g., PTP messages) with corrections to fields in messages based on aresidence time of the message within wireless communication system 410.Residence time correction (RTC) may be used to correct for the time ittakes a synchronization message (e.g., Sync, Follow_Up) to propagatethrough wireless communication system 410. For example, if a PTP messageis received from TSN 405 at node 1 435-a of wireless communicationsystem 410 at time t₁, sent to node 2 435-b, and transmitted from node 2435-b to another node of TSN 405 (e.g., an end point 415) at time t₂,one or more timing values within the PTP message may be adjusted basedon t₂-t₁, such that the propagation delay within wireless communicationsystem 410 is transparent to the TSN (e.g., the message appears to havebeen sent from the TSN 405 at t₂ with no propagation delay throughwireless communication system 410). Wireless communication system 410may act as a transparent clock for one-step synchronization messages ortwo-step synchronization messages.

FIG. 5A illustrates an example of a process flow 500 that supportswireless communication system enhancements for transparent and boundaryclocks in accordance with aspects of the present disclosure. In someexamples, process flow 500 may be implemented by aspects of wirelesscommunication networks 100, 200, or 400. For example, process flow 500may illustrate message flow and timing techniques in an exampleoperation of communication system 400, including communication betweenTSN 405-a, node 1 435-a, and node 2 435-b. For the purposes of theexample of FIG. 5A, node 1 435-a is an ingress point of wirelesscommunication system 410 and node 2 435-b is an egress point of wirelesscommunication system 410.

At 505, node 1 435-a receives a first ethernet frame that includes a PTPmessage 508. Node 1 may receive the first ethernet frame from anothercomponent of the communications system, such as TSN 405-a or an endpoint415 of TSN 405-a. The PTP message 508 may be a Sync message or aFollow_Up message. In some examples, the first ethernet frame is anytype of frame or data packet carrying a PTP message. In some examples,the ethernet frame including the PTP message 508 may be detected usingethertype in the ethernet header.

At 510, node 1 435-a determines an ingress time for PTP message 508.That is, node 1 435-a may record the time that it received PTP message508. This recorded time may be referred to as an ingress timestamp. Thetimestamp may be based on a clock known to the ingress point, node 1435-a, that may also be known at a potential egress point of wirelesscommunication system 410, such as node 2 435-b. For example, node 1435-a and node 2 435-b may have synchronized system clocks. In oneexample, node 1 435-a may be a UPF and node 2 435-b may be a UE 115, andthe UPF and UE 115 may synchronize their system clocks to wirelesscommunication system 410 (e.g., via wired or wireless synchronizationsignals).

At 515, node 1 435-a may generate a PDU for transmission to a secondnode of the wireless communication network, such as node 2 435-b. ThePDU may be based at least in part on the first ethernet frame, and maycarry the PTP message 508. The PDU may additionally carry the ingresstimestamp. That is, UE 115-a may generate a new ethernet PDU bymodifying the ethernet frame to include the ingress timestamp.

The ethernet frame may be modified in one of several ways. For example,the ingress timestamp may be appended to the ethernet frame of theethernet PDU. The ingress timestamp may be appended at the beginning ofthe frame, the end of the frame, or to a payload portion (e.g., PTPmessage) of the frame. For example, the ingress timestamp may beappended to the PTP message, such as in a suffix field to the PTPmessage. In other examples, the ingress timestamp may be appended to theethernet frame in other ways. Another way of modifying the ethernetframe to include the ingress timestamp may be to set a field in the PTPmessage to indicate a value associated with the ingress timestamp. Forexample, an originTimestamp field of a Sync PTP message (e.g., as partof a two-step synchronization message) may be overwritten with theingress timestamp. In another example, a field in a header of the SyncPTP message may be overwritten with the ingress timestamp. The field inthe header may be a correctionField. In another example, a typed linkvalue (TLV) of a PTP message may be overwritten with the ingresstimestamp. In some examples, the TLV may be organization specific.Setting a field in the PTP message with the ingress timestamp or a valuerelated to the ingress timestamp may override the typical informationthat the field carries.

Node 1 435-a sends the generated PDU 520 with the PTP message modifiedto include information related to the ingress timestamp to node 2 435-b.Node 1 435-a may send generated PDU 520 to more than one egress point ofthe wireless communication network. In some examples, the generated PDUmay be sent to more than one UE 115 or more than one UPF, for example,for multicast PTP messages.

Once node 2 435-b receives generated PDU 520, at 525 it may determinethe ingress time for the PTP message from generated PDU 520. Node 2435-b may determine the ingress time for the PTP message for thewireless communication network from a field in the PTP messageoverwritten with a value corresponding to the ingress time for the PTPmessage. At 530, UE 115-b may determine an adjustment for a timingparameter associated with the PTP message based at least in part on theingress time. Node 2 435-b may use the ingress timestamp or the valuerelated to the ingress timestamp for a residence time correctioncomputation.

In some examples, node 2 435-b may send a modified PDU 535 or ethernetframe associated with the ethernet PDU outside of the wirelesscommunication network (e.g., the 5G NR network). Node 2 435-b may havemodified the modified PDU 535 by removing any appended ingresstimestamps from the ethernet frame or altering a field in the PTPmessage that contained the information related to the ingress timestamp.The field may be altered by setting the field to a configured value(e.g., zero) if the field in the PTP message was used to send theinformation related to the ingress timestamp. Modified PDU 535 may alsohave an adjusted correction field in the PTP message based on theresidence time computation.

The example of FIG. 5A may be performed for any one-step or two-steptransparent clock. However, when the wireless communication network 410acts as a two-step transparent clock, a field may be set in the PTPmessage based on an ingress time for a different PTP message. Forexample, a field may be set in a PTP message based on a value in a fieldof a different PTP message that is received after the first PTP message.In one example, an originTimeStamp field may be set in a Sync messagebased on a preciseOriginTimeStamp field in a Follow_Up messageassociated with the Sync message. The Sync message may be modified withthis information after its initial reception at node 1 435-a or node 2435-b. In some cases, the Follow_Up message may be suppressed at node 1435-a or node 2 435-b (e.g., two-step synchronization messages may beconverted to one-step synchronization messages for transmission outsideof wireless communication network 410).

In some cases, an ingress node of wireless communication network 410 maysuppress sending one or more PTP messages to an egress node for overheadreduction. For example, if two-step synchronization messages are sentfrom TSN 405-a, the Sync message may be suppressed at the ingress node(e.g., node 1 435-a), and the egress node (e.g., node 2 435-b) mayregenerate the Sync message with appropriate timing based on the ingresstime. In some examples, the ingress or egress node may send anindication that a PDU session established between the nodes may carryPTP messages. In some examples, the indication may be sent using aninformation element and may only be applicable for ethernet PDUsessions. In some examples, a node (e.g., UE or UPF) may only look forPTP messages in a PDU session that has been indicated to carry PTPmessages. In some examples, an ingress or egress node may signal supportfor filtering of Sync messages. For example, an egress node may signalto an ingress node that it supports re-generating Sync messages, and theingress node may filter Sync messages based on the indication.Alternatively, an ingress node may signal support for filtering Syncmessages, and the egress point may re-generate Sync messages based onthe indication and information in other PTP messages (e.g., Follow_Upmessages).

Additional techniques address link delay from the TSN to the ingressnode. For example, the ingress node (e.g. node 1 435-a) may compensatefor link delay at 510 and 515. For example, wireless communicationnetwork 410 may operate as a peer-to-peer transparent clock and maycompensate for the link delay between TSN 405-a and node 1 435-a. Node 1435-a may compensate for the link delay by adjusting (e.g. adding,subtracting) the link delay from a field (e.g., originTimestamp,correctionField) in a PTP message prior to sending the PTP message inPDU 520 to the egress node (e.g., node 2 435-b). Alternatively, node 1435-a may adjust for the link delay by adjusting the ingress timesignaled to the egress node (e.g., in the overwritten field of the PTPmessage or in the appended ingress time). Thus, when the egress nodecorrects for the ingress time, the link delay is also corrected for.

FIG. 5B illustrates an example of a process flow 550 that supportswireless communication system enhancements for transparent and boundaryclocks in accordance with aspects of the present disclosure. In someexamples, process flow 550 may be implemented by aspects of wirelesscommunication networks 100, 200, or 400. For example, process flow 550may illustrate message flow and timing techniques in an exampleoperation of communication system 400, including communication betweenTSN 405-b, node 1 435-c, and node 2 435-d. For the purposes of theexample of FIG. 5A, node 1 435-c is an ingress point of wirelesscommunication system 410 and node 2 435-d is an egress point of wirelesscommunication system 410.

At 560, node 1 435-c receives a first ethernet frame that includes afirst PTP message 555. Node 1 may receive the first ethernet frame fromanother component of the communications system, such as TSN 405-b or anendpoint 415 of TSN 405-b. In some examples, receiving the firstethernet frame may include identifying time-frequency resources overwhich a control or data channel is transmitted, demodulatingtransmission over those time-frequency resources, and decoding thedemodulated transmission to obtain bits that indicate the downlinktransmission.

The first PTP message 555 may be a Sync message or a Follow_Up message.In some examples, the first ethernet frame is any type of frame or datapacket carrying a PTP message. In some examples, the ethernet frameincluding the first PTP message 555 may be detected using ethertype inthe ethernet header.

At 565, node 1 435-c determines an ingress time for the first PTPmessage 555. That is, node 1 435-c may record the time that it receivedthe first PTP message 555. This recorded time may be referred to as aningress timestamp. The timestamp may be based on a clock known to theingress point, node 1 435-c, that may also be known at a potentialegress point of wireless communication system 410, such as node 2 435-d.For example, node 1 435-c and node 2 435-d may have synchronized systemclocks. In one example, node 1 435-c may be a UPF and node 2 435-d maybe a UE 115, and the UPF and UE 115 may synchronize their system clocksto wireless communication system 410 (e.g., via wired or wirelesssynchronization signals).

At 575, node 1 435-c may receive a second ethernet frame that includes asecond PTP message 570. Node 1 may receive the second ethernet framefrom another component of the communications system, such as TSN 405-bor an endpoint 415 of TSN 405-b. In some examples, receiving the secondethernet frame may include identifying time-frequency resources overwhich a control or data channel is transmitted, demodulatingtransmission over those time-frequency resources, and decoding thedemodulated transmission to obtain bits that indicate the downlinktransmission.

At 580, node 1 435-c may generate a PDU for transmission to a secondnode of the wireless communication network, such as node 2 435-d. ThePDU may be based at least in part on based at least in part on thesecond ethernet frame, the PDU comprising a value corresponding to theingress time for the first PTP message 555. The PDU may additionallycarry the ingress timestamp. That is, UE 115-a may generate a newethernet PDU by modifying the ethernet frame to include the ingresstimestamp.

The ethernet frame may be modified in one of several ways. For example,the ingress timestamp may be appended to the ethernet frame of theethernet PDU. For example, generating the PDU may include appending thevalue corresponding to the ingress time for the first PTP message to thesecond ethernet frame in the PDU. The ingress timestamp may be appendedat the beginning of the frame, the end of the frame, or to a payloadportion (e.g., PTP message) of the frame. For example, the ingresstimestamp may be appended to the PTP message, such as in a suffix fieldto the PTP message. In other examples, the ingress timestamp may beappended to the ethernet frame in other ways. Additionally oralternatively, generating the PDU may further include modifying thesecond ethernet frame by overwriting a timestamp field of the second PTPmessage with the value corresponding to the ingress time, modifying thesecond ethernet frame by overwriting a field of a header of the secondPTP message with the value corresponding to the ingress time, ormodifying the second ethernet frame by overwriting a type linked value(TLV) of the second PTP message with the value corresponding to theingress time.

Node 1 435-c sends the generated PDU 585 to node 2 435-d. Node 1 435-cmay send the generated PDU 520 to more than one egress point of thewireless communication network. In some examples, the generated PDU maybe sent to more than one UE 115 or more than one UPF, for example, formulticast PTP messages.

The example of FIG. 5B may be performed for a two-step transparentclock. For example, when the wireless communication network 410 acts asa two-step transparent clock, a field may be set in the PTP messagebased on an ingress time for a different PTP message, such as the firstPTP message 555. For example, a field may be set in the second PTPmessage based on a value in a field of the first PTP message, differentfrom the second PTP message. In one example, an originTimeStamp fieldmay be set in a Sync message based on a preciseOriginTimeStamp field ina Follow_Up message associated with the Sync message. The Sync messagemay be modified with this information after its initial reception atnode 1 435-c or node 2 435-d. In some cases, the Follow_Up message maybe suppressed at node 1 435-c or node 2 435-d (e.g., two-stepsynchronization messages may be converted to one-step synchronizationmessages for transmission outside of wireless communication network410).

In some cases, an ingress node of wireless communication network 410 maysuppress sending one or more PTP messages to an egress node for overheadreduction. For example, if two-step synchronization messages are sentfrom TSN 405-b, the Sync message may be suppressed at the ingress node(e.g., node 1 435-c), and the egress node (e.g., node 2 435-d) mayregenerate the Sync message with appropriate timing based on the ingresstime. In some examples, the ingress or egress node may send anindication that a PDU session established between the nodes may carryPTP messages. In some examples, the indication may be sent using aninformation element and may only be applicable for ethernet PDUsessions. In some examples, a node (e.g., UE or UPF) may only look forPTP messages in a PDU session that has been indicated to carry PTPmessages. In some examples, an ingress or egress node may signal supportfor filtering of Sync messages. For example, an egress node may signalto an ingress node that it supports re-generating Sync messages, and theingress node may filter Sync messages based on the indication.Alternatively, an ingress node may signal support for filtering Syncmessages, and the egress point may re-generate Sync messages based onthe indication and information in other PTP messages (e.g., Follow_Upmessages).

Additional techniques address link delay from the TSN to the ingressnode. For example, the ingress node (e.g. node 1 435-c) may compensatefor link delay at 565 and 580. For example, wireless communicationnetwork 410 may operate as a peer-to-peer transparent clock and maycompensate for the link delay between TSN 405-b and node 1 435-c. Node 1435-c may compensate for the link delay by adjusting (e.g. adding orsubtracting) the link delay from a field (e.g., originTimestamp,correctionField) in a PTP message prior to sending the PTP message inPDU 585 to the egress node (e.g., node 2 435-d). Alternatively, node 1435-c may adjust for the link delay by adjusting the ingress timesignaled to the egress node (e.g., in the overwritten field of the PTPmessage or in the appended ingress time). Thus, when the egress nodecorrects for the ingress time, the link delay is corrected.

In some examples, the process flow 550 may further include suppressingtransmission of the first PTP message to the second node. Other examplesof the process flow 550 may include suppressing transmission of thefirst PTP message to the second node or receiving an indicator ofsupport of the second node for suppressing transmission of the first PTPmessage to the second node. In some examples, the indicator isassociated with a PDU session associated with the first and second PTPmessages or with the PDU. Some examples of the process flow 550 mayfurther include signaling that the first node can filter Sync messagesassociated with the PTP message.

FIG. 6 illustrates an example of a communication system 600 thatsupports wireless communication system enhancements for transparent andboundary clocks in accordance with aspects of the present disclosure. Insome examples, communication system 600 may implement aspects ofcommunication systems 100, 200, or 400. FIG. 6 illustrates an examplewhere a wireless communication system 610 of communication system 600may act as a boundary clock.

Communication system 600 may be an example of communication system 100,200, or 400 of FIGS. 1, 2, and 4, respectively. Communication system 600may include a TSN 605, a wireless communication network 610, one or moreTSN bridges 620, and endpoints 615-a and 615-b (collectively referred toherein as endpoints 615). In other examples, other numbers of TSNs 605,wireless communication system 610, TSN bridges 620, and endpoints 615may be part of communication system 600, which may be examples ofaspects of the respective components as described above with referenceto FIGS. 1, 2, and 4.

In another approach for synchronization via wireless communicationsystem 610, wireless communication system 610 acts as a boundary clock.For example, clocks 630 for one or more timing domains within TSN 605may act as master clocks, such as a master clock 1 630-a and a masterclock 2 630-b. Some clocks within wireless communication network 610 mayact as slave clocks 635-a and 635-b, while other clocks 640-a and 640-bact as master clocks. In some examples, the same clocks act both asslave and master clocks. The slave clocks 635 within wirelesscommunication network 610 may slave to master clocks 630 in TSN 605(e.g., via received synchronization messages). The master clocks 640within wireless communication network 610 may be based on the slaveclocks 635 within wireless communication network 610. For example, amaster clock 640 within a UE may synchronize its system clock withwireless communication network 610 using transmitted synchronizationsignals (e.g., synchronization blocks), and may a maintain master clock640 to be a synchronized version of a slave clock 635 via internalsignaling of a correspondence of the slave clock 635 with the systemclock. Clocks within endpoints 615-a and 615-b may act as slave clocks645-a and 645-b, respectively, that slave to master clocks 640 inwireless communication system 610. In another part of the communicationsystem 600. For example, a nodes of wireless communication system 610maintaining master clock 640-a may transmit synchronization messages(e.g., PTP messages) to slave clock 645-a according to the timing ofmaster clock 640-a. That is, master clock 640-a may be synchronized tomaster clock 630-a, but may transmit PTP messages independently of PTPmessages sent by master clock 630-a.

In some examples, the UE or UPF may identify relevant timing domains bytracking timing domain information in received PTP messages andoptionally tracking corresponding VLAN tags associated with ethernetpackets containing the PTP messages. The UE or UPF may save the domaininformation in a received PTP message contained in domainNumber field inheader of the PTP message. Specific examples for timing domaininformation in PTP messages may include that the UE may save domaininformation in a Pdelay_req message contained in domainNumber field inheader of the Pdelay_req message or that UE may save domain informationin an Announce message contained in domainNumber field in header of theAnnounce message. A list of relevant timing domains may include thesaved timing domains. The UE or UPF may then maintain a master clock forthe list of relevant timing domains saved from PTP messages. A timingdomain may be removed from a list of relevant timing domains if theassociated timing domain is not part of any PTP messages for a durationsatisfying a threshold (e.g., TimingDomain_TimeoutDuration).

FIG. 7 shows a block diagram 700 of a wireless device 705 that supportstiming synchronization in accordance with various aspects of the presentdisclosure. Wireless device 705 may be an example of aspects of a UE115, an adaptor/translator 220, or a UPF 225 as described with referenceto FIGS. 1, 2, and 4-6. Wireless device 705 may include receiver 710,communication manager 715, and transmitter 720. Wireless device 705 mayalso include a processor. Each of these components may be incommunication with one another (e.g., via one or more buses).

Receiver 710 may receive information 725 such as packets, ethernetframes, user data, or control information associated with variousinformation channels (e.g., control channels, data channels, andinformation related to wireless transmission timing based on timingadvance values in shortened transmission time interval transmissions,etc.). Information 730 may be passed on to other components of device700. Receiver 710 may be an example of aspects of a transceiver 1135described with reference to FIG. 10.

In some examples, receiver 710 may receiving a first ethernet framecomprising a PTP message. In some examples, the PTP message is a firstPTP message. In other examples, receiver 701 may receive, from a secondnode of the wireless communication network, a session connectivitymessage associated with a PDU session, the session connectivity messagecomprising an indicator that the PDU session supports PTP messages. Insome examples, receiver 710 may also receive a second ethernet framecomprising a second PTP message associated with the first PTP message.

In some examples, receiver 710 may receive, from a second node of thewireless communication network, a PDU associated with first and secondethernet frames received at the second node, the first ethernet framecomprising a first PTP message, and the second ethernet frame comprisinga second PTP message. In another example, receiver 710 may receive, fromone or more UEs served by the first node, an indicator of one or moretiming domains to be supported by the one or more UEs. In anotherexample, receiver 710 may receive, from a second node of the wirelesscommunication network, an indicator of one or more supported timingdomains.

Communication manager 715 may be an example of aspects of the wirelesscommunications network 510 described with reference to FIGS. 5 and 6.Communication manager 715 and/or at least some of its varioussub-components may be implemented in hardware, software executed by aprocessor, firmware, or any combination thereof. If implemented insoftware executed by a processor, the functions of the communicationmanager 715 and/or at least some of its various sub-components may beexecuted by a general-purpose processor, a digital signal processor(DSP), an application-specific integrated circuit (ASIC), anfield-programmable gate array (FPGA) or other programmable logic device,discrete gate or transistor logic, discrete hardware components, or anycombination thereof designed to perform the functions described in thepresent disclosure. The communication manager 715 and/or at least someof its various sub-components may be physically located at variouspositions, including being distributed such that portions of functionsare implemented at different physical locations by one or more physicaldevices. In some examples, communication manager 715 and/or at leastsome of its various sub-components may be a separate and distinctcomponent in accordance with various aspects of the present disclosure.In other examples, communication manager 715 and/or at least some of itsvarious sub-components may be combined with one or more other hardwarecomponents, including but not limited to an I/O component, atransceiver, a network server, another computing device, one or moreother components described in the present disclosure, or a combinationthereof in accordance with various aspects of the present disclosure.

Communication manager 715 may determine an ingress time for the PTPmessage received at the first node, which may be determined frominformation 730. Communication manager 715 may also generate a PDU fortransmission to a second node of the wireless communication networkbased at least in part on the first ethernet frame by overwriting afield in the PTP message with a value corresponding to the ingress timefor the PTP message.

In examples where communication manager 715 is acting as an egress node,communication manager 715 may determine an ingress time for the PTPmessage for the wireless communication network from a field in the PTPmessage overwritten with a value corresponding to the ingress time forthe PTP message. Communication manager 715 may also determine anadjustment for a timing parameter associated with the PTP message basedat least in part on the ingress time.

In another example, communication manager 715 may monitor one or morePDUs received from the second node for PTP messages based at least inpart on the indicator that the PDU session supports PTP messages.Communication manager 715 may also identify a PTP message in a PDU ofthe one or more PDUs based at least in part on the monitoring.Communication manager 715 may also identify a PTP message in a PDU ofthe one or more P receiving, from one or more UEs served by the firstnode, an indicator of one or more timing domains to be supported by theone or more UEs.

In some examples, communication manager 715 may determine an ingresstime for the first PTP message received at the first node and generate aPDU for transmission to a second node of the wireless communicationnetwork based at least in part on the second ethernet frame, the PDUcomprising a value corresponding to the ingress time for the first PTPmessage. In some examples, the PDU comprises a suffix field whichincludes the ingress time for the first PTP message.

In another example, communication manager 715 may determine an ingresstime for the first PTP message received at the second node based atleast in part on the PDU (e.g., based on one or more octets of the PDUassociated with the ingress time). Communication manager 715 maydetermine an adjustment for a timing parameter of the second PTP messagebased at least in part on the ingress time.

Communication manager 715 may determine a link delay time for the PTPmessage between transmission from the time sensitive network andreception by the first node in some examples. Communication manager 715may also generate a PDU for transmission to a second node of thewireless communication network based at least in part on adjusting afield of the PTP message according to a link delay.

In another example, communication manager 715 may include identify oneor more relevant timing domains for the wireless communication networkbased at least in part on the PTP message. Communication manager 715 maymaintain a boundary clock for each of the one or more timing domains.Communication manager 715 may provide information 735 to transmitter 720for transmission.

Transmitter 720 may transmit signals 740 generated by other componentsof the device. In some examples, transmitter 720 may be collocated withreceiver 710 in a transceiver module. For example, transmitter 720 maybe an example of aspects of the transceiver 1135 described withreference to FIG. 10. The transmitter 720 may include a single antenna,or it may include a set of antennas. For example, transmitter 720 maysend the PDU to a second node.

In some examples, transmitter 720 may send, to a second node of thewireless communication network, a session connectivity messageassociated with a PDU session for conveying the frame, the sessionconnectivity message comprising an indicator that the PDU sessionsupports PTP messages. Transmitter 720 may send, to the second node, aPDU comprising the PTP message. In another example, transmitter 720 maysend, for each timing domain of the one or more timing domains, anidentifier of the timing domain and timing information associated withthe timing domain.

FIG. 8 shows a block diagram 800 of a wireless device 805 that supportswireless communication system timing synchronization in accordance withvarious aspects of the present disclosure. Wireless device 805 may be anexample of aspects of a UE 115, an adaptor/translator 220, or a UPF 225as described with reference to FIGS. 1, 2, and 4-7. Wireless device 805may include receiver 810, communication manager 815, and transmitter820. Wireless device 805 may also include a processor. Each of thesecomponents may be in communication with one another (e.g., via one ormore buses).

Receiver 810 may receive information 840 such as packets, user data, orcontrol information associated with various information channels (e.g.,control channels, data channels, and information related to wirelesstransmission timing based on timing advance values in shortenedtransmission time interval transmissions, etc.). Information 845 may bepassed on to other components of wireless device 805. Receiver 810 maybe an example of aspects of the transceiver 1035 described withreference to FIG. 10.

Communication manager 815 may be an example of aspects of thecommunication manager 715 and 1015 described with reference to FIGS. 7and 10. Communication manager 815 may also include timing manager 820,PDU manager 825, and transmission parameter module 835. Communicationmanager 815 may process information 845 to generate information 850 fortransmission by transmitter 820.

Timing manager 820 may determine an ingress time for the PTP messagereceived at the first node. In some examples, determining an ingresstime for the PTP message for the wireless communication network is froma field in the PTP message overwritten with a value corresponding to theingress time for the PTP message. Timing manager 820 may also determinean adjustment for a timing parameter associated with the PTP messagebased at least in part on the ingress time.

In some examples, timing manager 820 may determine an egress time for asecond ethernet frame associated with the PTP message from the firstnode and determine a residence time correction for the ethernet framecomprising the PTP message time by subtracting the ingress time from theegress time. In other examples, timing manager 820 may identify one ormore relevant timing domains for the wireless communication networkbased at least in part on the PTP message. Timing manager 820 mayidentify a network tag in a frame associated with the PTP message,wherein identifying the one or more timing domains is further based atleast in part on the network tag. Timing manager 820 may also remove atiming domain from the one or more timing domains based at least in parton the PTP message.

PDU manager 825 may generate a PDU for transmission to a second node ofthe wireless communication network based at least in part on the firstethernet frame by overwriting a field in the PTP message with a valuecorresponding to the ingress time for the PTP message. PDU manager 825may also overwrite a timestamp field of the Sync PTP message with thevalue corresponding to the ingress time. Alternatively, PDU manager 825may overwrite a field of a header of the Sync PTP message with the valuecorresponding to the ingress time. PDU manager 825 may overwrite a TLVof the PTP message with the value corresponding to the ingress time.

In some examples, PDU manager 825 may provide an indication to thesecond node that an associated PDU session may carry PTP messages. Inanother example, PDU manager 825 may adjust the modified version of thePTP message by setting the overwritten field in the PTP message to aconfigured value. PDU manager 825 may generate a PDU for transmission toa second node of the wireless communication network based at least inpart on adjusting a field of the PTP message according to a link delay.

In another example, PDU manager 825 may monitor one or more PDUsreceived from the second node for PTP messages based at least in part onthe indicator that the PDU session supports PTP messages and identify aPTP message in a PDU of the one or more PDUs based at least in part onthe monitoring.

Link delay manager 830 adjust the ingress time for the PTP message toaccount for a link delay associated with the PTP message. In someexamples, link delay manager 830 may also determine a link delay timefor the PTP message between transmission from the time sensitive networkand reception by the first node.

Transmitter 820 may transmit signals 855 generated by other componentsof the device. In some examples, the transmitter 820 may be collocatedwith a receiver 810 in a transceiver module. For example, thetransmitter 820 may be an example of aspects of the transceiver 1035described with reference to FIG. 10. The transmitter 820 may include asingle antenna, or it may include a set of antennas.

FIG. 9 shows a block diagram 900 of a communication manager 915 thatsupports wireless transmission timing based on timing advance values inshortened transmission time interval transmissions in accordance withvarious aspects of the present disclosure. The communication manager 905may be an example of aspects of a communication manager 715, acommunication manager 815, or a communication manager 1015 describedwith reference to FIGS. 7, 8, and 10. The communication manager 915 mayinclude receiver 920. Each of these modules may communicate, directly orindirectly, with one another (e.g., via one or more buses).

The receiver 910 may receive one or more signals 940 (e.g., from atransmitter of another device such as a second node of the wirelesscommunication network). In some examples, the signal 940 may be a firstethernet frame including a PTP message. In some examples, the receiver910 may receive, from a second node of the wireless communicationnetwork, a signal 940 that is a PDU including a PTP message. In someexamples, the signal 940 may include a session connectivity messageassociated with a PDU session, the session connectivity messageincluding an indicator that the PDU session supports PTP messages.

In some examples, the receiver 910 may receive a second ethernet frameincluding a second PTP message associated with the first PTP message asone or more signals 940. In some examples, the signal 940, from a secondnode of the wireless communication network, a PDU associated with firstand second ethernet frames received at the second node, the firstethernet frame including a first PTP message, and the second ethernetframe including a second PTP message. In some examples, the receiver 910may receive, from a time sensitive network, an ethernet frame includinga PTP message in the one or more signals 940.

In some examples, the receiver 910 may receive, from one or more UEsserved by the first node, an indicator of one or more timing domains tobe supported by the one or more UEs in the one or more signals 940. Insome examples, the receiver 910 may receive an indication that a PDUsession associated with the PTP message carries PTP messages in the oneor more signals 940. In some examples, the one or more signals 940 mayinclude an indicator of support of the second node for suppressingtransmission of the first PTP message to the second node. In someexamples, the one or more signals 940 may include, from the second node,timing information for the one or more timing domains.

The receiver 910 may provide the one or more signals, including a PTPmessage, to the timing manager 935, as information 945. The timingmanager 935 may determine an ingress time for the PTP message receivedat the first node, from information 945. In some examples, the timingmanager 935 may determine an ingress time for the PTP message for thewireless communication network from a field in the PTP messageoverwritten with a value corresponding to the ingress time for the PTPmessage or from a field appended to the PTP message. In some examples,the timing manager 935 may determine an adjustment for a timingparameter associated with the PTP message based on the ingress time. Insome examples, the timing manager 935 may determine an ingress time forthe first PTP message received at the second node based on the PDU. Thetiming manager 935 may provide information 950 to the PDU manager 920,which may include the ingress time for the PTP message.

In some examples, the timing manager 935 may determine an adjustment fora timing parameter of the second PTP message based on the ingress time.In some examples, the timing manager 935 may identify one or morerelevant timing domains for the wireless communication network based onthe PTP message. In some examples, the timing manager 935 may maintain aboundary clock for each of the one or more timing domains. In someexamples, the timing manager 935 may determine an egress time for asecond ethernet frame including the PTP message from the first node. Insome examples, the timing manager 935 may determine a residence timecorrection for the ethernet frame including the PTP message time bysubtracting the ingress time from the egress time. In some examples, theinformation 950 to the PDU manager 920 may include an adjustment for atiming parameter of the second PTP message.

In some examples, the timing manager 935 may determine an egress timefor a third ethernet frame including a modified version of the first PTPmessage. In some examples, the timing manager 935 may identify a networktag in a frame associated with the PTP message, where identifying theone or more timing domains is further based on the network tag. In someexamples, the timing manager 935 may remove a timing domain from the oneor more timing domains based on the PTP message. In some examples, theinformation 950 to the PDU manager 920 may include the egress time forthe third ethernet frame including the modified version of the first PTPmessage.

The PDU manager 920 may generate a PDU for transmission to a second nodeof the wireless communication network based on the first ethernet frameby overwriting a field in the PTP message with a value corresponding tothe ingress time for the PTP message or by appending a suffix to the PTPmessage. In some examples, the PDU manager 920 generates the PDU usingthe information 950. In some examples, the PDU manager 920 may monitorone or more PDUs received from the second node for PTP messages based onthe indicator that the PDU session supports PTP messages. In someexamples, the PDU manager 920 may identify a PTP message in a PDU of theone or more PDUs based on the monitoring.

In some examples, the PDU manager 920 may generate a PDU fortransmission to a second node of the wireless communication networkbased on the second ethernet frame, the PDU including a valuecorresponding to the ingress time for the first PTP message. In someexamples, the PDU manager 920 may generate a PDU for transmission to asecond node of the wireless communication network based on adjusting afield of the PTP message according to a link delay.

In some examples, the PDU manager 920 may overwrite a timestamp field ofthe Sync PTP message with the value corresponding to the ingress time.In some examples, the PDU manager 920 may overwrite a field of a headerof the Sync PTP message with the value corresponding to the ingresstime. In some examples, the PDU manager 920 may overwrite a type linkedvalue (TLV) of the PTP message with the value corresponding to theingress time.

In some examples, the PDU manager 920 may provide an indication to thesecond node that an associated PDU session may carry PTP messages. Insome examples, the PDU manager 920 may adjust the modified version ofthe PTP message by setting the overwritten field in the PTP message to aconfigured value. In some examples, the PDU manager 920 may generate thePDU by inserting a value corresponding to the ingress time for the PTPmessage. In some examples, the PDU manager 920 may append the valuecorresponding to the ingress time for the first PTP message to thesecond ethernet frame (e.g., as a suffix to the second PTP message) inthe PDU.

In some examples, the PDU manager 920 may modify the second ethernetframe by overwriting a timestamp field of the second PTP message withthe value corresponding to the ingress time. In some examples, the PDUmanager 920 may modify the second ethernet frame by overwriting a fieldof a header of the second PTP message with the value corresponding tothe ingress time. In some examples, the PDU manager 920 may modify thesecond ethernet frame by overwriting a type linked value (TLV) of thesecond PTP message with the value corresponding to the ingress time.

The link delay manager 930 and the PDU manager 920 may exchangeinformation 955, which may include a PDU, timestamps, or a link delayassociated with the PTP message. The link delay manager 930 maydetermine a link delay time for the PTP message between transmissionfrom the time sensitive network and reception by the first node. In someexamples, the link delay manager 930 may adjust the ingress time for thePTP message to account for a link delay associated with the PTP message.In some examples, the link delay manager 930 also receives information945 from the receiver 910 or information 956 from the transmitter 925,such as an egress time for a PDU message.

In some examples, the PDU manager 920 may adjust the ingress time forthe PTP message to account for a link delay associated with the PTPmessage. In some examples, the PDU manager 920 may suppress transmissionof the first PTP message to the second node. In some examples, the PDUmanager 920 may adjust the modified version of the second PTP message bysetting the overwritten field in the PTP message to a configured value.

The PDU manager 920 may provide information 960 to the transmitter 925.In some examples, the link delay manager 930 may provide information 965to the transmitter 925. The transmitter 925 may send information 970,such as the PDU, to the second node. The PDU may include the PTPmessage. In some examples, the transmitter 925 may transmit, to a secondnode of the wireless communication network, a session connectivitymessage associated with a PDU session for conveying the frame, thesession connectivity message including an indicator that the PDU sessionsupports PTP messages.

In some examples, the transmitter 925 may transmit, for each timingdomain of the one or more timing domains, an identifier of the timingdomain and timing information associated with the timing domain. In someexamples, the transmitter 925 may signal that the first node can filterSync messages associated with the PTP message. In some examples,transmitting the second ethernet frame to a time sensitive network,where the second ethernet frame includes a modified version of the PTPmessage.

In some examples, the transmitter 925 may transmit the second ethernetframe to a time sensitive network, where a correction field of themodified version of the PTP message is adjusted by the residence timecorrection. In some examples, the transmitter 925 may provide anindication to the second node that an associated PDU session may carryPTP messages. In some examples, the transmitter 925 may signal that thefirst node can filter Sync messages associated with the PTP message.

In some examples, the transmitter 925 may transmit the third ethernetframe including a modified version of the second PTP message thatidentifies an adjustment to a time sensitive network, where a correctionfield of the modified version of the second PTP message is modifiedusing the residence time correction. In some examples, the transmitter925 may send a second PTP message to a node of a time sensitive networkassociated with a timing domain of the one or more timing domains basedon the respective boundary clock associated with the timing domain.

In some examples, the transmitter 925 may transmit, to a second node ofthe wireless communication network, an indicator of the network tag withthe identifier of the timing domain. In some examples, the transmitter925 may send a PDU to the third node including a modified version of thePTP message based on the timing domain being one of the one or moretiming domains.

FIG. 10 shows a diagram of a system 1000 including a device 1005 thatsupports wireless transmission timing based on timing advance values inshortened transmission time interval transmissions in accordance withvarious aspects of the present disclosure. Device 1005 may be an exampleof or include the components of wireless device 705, wireless device805, or a UE 115 as described above, e.g., with reference to FIGS. 1, 7,and 8. Device 1005 may include components for bi-directional voice anddata communications including components for transmitting and receivingcommunications, including Communications manager 1015, processor 1020,memory 1025, software 1030, transceiver 1035, antenna 1040, and I/Ocontroller 1045. These components may be in electronic communication viaone or more busses (e.g., bus 1010). Device 1005 may communicatewirelessly with one or more base stations 105.

The communications manager 1010 may receive a first ethernet frameincluding a PTP message, determine an ingress time for the PTP messagereceived at the first node, generate a PDU for transmission to a secondnode of the wireless communication network based on the first ethernetframe by overwriting a field in the PTP message with a valuecorresponding to the ingress time for the PTP message, and send the PDUto the second node.

The communications manager 1010 may also receive, from a second node ofthe wireless communication network, a PDU including a PTP message,determine an ingress time for the PTP message for the wirelesscommunication network from a field in the PTP message overwritten with avalue corresponding to the ingress time for the PTP message, anddetermine an adjustment for a timing parameter associated with the PTPmessage based on the ingress time.

The communications manager 1010 may also receive a frame including a PTPmessage, transmit, to a second node of the wireless communicationnetwork, a session connectivity message associated with a PDU sessionfor conveying the frame, the session connectivity message including anindicator that the PDU session supports PTP messages, and send, to thesecond node, a PDU including the PTP message.

The communications manager 1010 may also receive, from a second node ofthe wireless communication network, a session connectivity messageassociated with a PDU session, the session connectivity messageincluding an indicator that the PDU session supports PTP messages,monitor one or more PDUs received from the second node for PTP messagesbased on the indicator that the PDU session supports PTP messages, andidentify a PTP message in a PDU of the one or more PDUs based on themonitoring.

The communications manager 1010 may also receive, at a first node of awireless communication network, a first ethernet frame including a firstPTP message, receive a second ethernet frame including a second PTPmessage associated with the first PTP message, determine an ingress timefor the first PTP message received at the first node, generate a PDU fortransmission to a second node of the wireless communication networkbased on the second ethernet frame, the PDU including a valuecorresponding to the ingress time for the first PTP message, andtransmit the PDU to the second node.

The communications manager 1010 may also receive, from a second node ofthe wireless communication network, a PDU associated with first andsecond ethernet frames received at the second node, the first ethernetframe including a first PTP message, and the second ethernet frameincluding a second PTP message, determine an ingress time for the firstPTP message received at the second node based on the PDU, and determinean adjustment for a timing parameter of the second PTP message based onthe ingress time.

The communications manager 1010 may also receive, from a time sensitivenetwork, an ethernet frame including a PTP message, determine a linkdelay time for the PTP message between transmission from the timesensitive network and reception by the first node, generate a PDU fortransmission to a second node of the wireless communication networkbased on adjusting a field of the PTP message according to a link delay,transmit the PDU to the second node, receive a PTP message, identify oneor more relevant timing domains for the wireless communication networkbased on the PTP message, and maintain a boundary clock for each of theone or more timing domains.

The communications manager 1010 may also receive, from one or more UEsserved by the first node, an indicator of one or more timing domains tobe supported by the one or more UEs and transmit, for each timing domainof the one or more timing domains, an identifier of the timing domainand timing information associated with the timing domain.

The communications manager 1010 may also receive, from a second node ofthe wireless communication network, an indicator of one or more timingdomains supported by a third node of the wireless communication network.The communications manager 1010 may also process one or more PTPmessages associated with a PDU session according to the one or moretiming domains supported by the third node. In some examples, the secondand third nodes may be a same node.

Transceiver 1020 may communicate bi-directionally, via one or moreantennas, wired, or wireless links as described above. For example, thetransceiver 1020 may represent a wireless transceiver and maycommunicate bi-directionally with another wireless transceiver. Thetransceiver 1020 may also include a modem to modulate the packets andprovide the modulated packets to the antennas for transmission, and todemodulate packets received from the antennas.

In some cases, the wireless device may include a single antenna 1025.However, in some cases the device may have more than one antenna 1025,which may be capable of concurrently transmitting or receiving multiplewireless transmissions.

The memory 1030 may include RAM, ROM, or a combination thereof. Thememory 1030 may store computer-readable code 1035 including instructionsthat, when executed by a processor (e.g., the processor 1040) cause thedevice to perform various functions described herein. In some cases, thememory 1030 may contain, among other things, a BIOS which may controlbasic hardware or software operation such as the interaction withperipheral components or devices.

The processor 1040 may include an intelligent hardware device, (e.g., ageneral-purpose processor, a DSP, a CPU, a microcontroller, an ASIC, anFPGA, a programmable logic device, a discrete gate or transistor logiccomponent, a discrete hardware component, or any combination thereof).In some cases, the processor 1040 may be configured to operate a memoryarray using a memory controller. In other cases, a memory controller maybe integrated into the processor 1040. The processor 1040 may beconfigured to execute computer-readable instructions stored in a memory(e.g., the memory 1030) to cause the device 1005 to perform variousfunctions (e.g., functions or tasks supporting wireless communicationsystem enhancements for transparent and boundary clocks).

The I/O controller 1050 may manage input and output signals for thedevice 1005. The I/O controller 1050 may also manage peripherals notintegrated into the device 1005. In some cases, the I/O controller 1050may represent a physical connection or port to an external peripheral.In some cases, the I/O controller 1050 may utilize an operating systemsuch as iOS®, ANDROID®, MS-DOS®, MS-WINDOWS®, OS/2®, UNIX®, LINUX®, oranother known operating system. In other cases, the I/O controller 1050may represent or interact with a modem, a keyboard, a mouse, atouchscreen, or a similar device. In some cases, the I/O controller 1050may be implemented as part of a processor. In some cases, a user mayinteract with the device 1005 via the I/O controller 1050 or viahardware components controlled by the I/O controller 1050.

The code 1035 may include instructions to implement aspects of thepresent disclosure, including instructions to support wirelesscommunications. The code 1035 may be stored in a non-transitorycomputer-readable medium such as system memory or other type of memory.In some cases, the code 1035 may not be directly executable by theprocessor 1040 but may cause a computer (e.g., when compiled andexecuted) to perform functions described herein.

FIG. 11 shows a flowchart illustrating a method 1100 that supportswireless communication system enhancements for transparent and boundaryclocks in accordance with aspects of the present disclosure. Theoperations of method 1100 may be implemented by a UE 115, a UPF, orassociated components as described herein. For example, the operationsof method 1100 may be performed by a communications manager as describedwith reference to FIGS. 2 and 4-10. In some examples, a UE or UPF mayexecute a set of instructions to control the functional elements of theUE or UPF to perform the functions described below. Additionally oralternatively, a UE or UPF may perform aspects of the functionsdescribed below using special-purpose hardware.

At 1105, the UE or UPF may receive a first ethernet frame including aPTP message. The operations of 1105 may be performed according to themethods described herein. In some examples, aspects of the operations of1105 may be performed by a receiver as described with reference to FIGS.7 through 10.

At 1110, the UE or UPF may determine an ingress time for the PTP messagereceived at the first node. The operations of 1110 may be performedaccording to the methods described herein. In some examples, aspects ofthe operations of 1110 may be performed by a timing manager as describedwith reference to FIGS. 7 through 10.

At 1115, the UE or UPF may generate a PDU for transmission to a secondnode of the wireless communication network based on the first ethernetframe by overwriting a field in the PTP message with a valuecorresponding to the ingress time for the PTP message. The operations of1115 may be performed according to the methods described herein. In someexamples, aspects of the operations of 1115 may be performed by a PDUmanager as described with reference to FIGS. 7 through 10.

At 1120, the UE or UPF may send the PDU to the second node. Theoperations of 1120 may be performed according to the methods describedherein. In some examples, aspects of the operations of 1120 may beperformed by a transmitter as described with reference to FIGS. 7through 10.

FIG. 12 shows a flowchart illustrating a method 1200 that supportswireless communication system enhancements for transparent and boundaryclocks in accordance with aspects of the present disclosure. Theoperations of method 1200 may be implemented by a UE 115, a UPF, orassociated components as described herein. For example, the operationsof method 1200 may be performed by a communications manager as describedwith reference to FIGS. 2 and 4-10. In some examples, a UE or UPF mayexecute a set of instructions to control the functional elements of theUE or UPF to perform the functions described below. Additionally oralternatively, a UE or UPF may perform aspects of the functionsdescribed below using special-purpose hardware.

At 1205, the UE or UPF may receive, from a second node of the wirelesscommunication network, a PDU including a PTP message. The operations of1205 may be performed according to the methods described herein. In someexamples, aspects of the operations of 1205 may be performed by areceiver as described with reference to FIGS. 7 through 10.

At 1210, the UE or UPF may determine an ingress time for the PTP messagefor the wireless communication network from a field in the PTP messageoverwritten with a value corresponding to the ingress time for the PTPmessage. The operations of 1210 may be performed according to themethods described herein. In some examples, aspects of the operations of1210 may be performed by a timing manager as described with reference toFIGS. 7 through 10.

At 1215, the UE or UPF may determine an adjustment for a timingparameter associated with the PTP message based on the ingress time. Theoperations of 1215 may be performed according to the methods describedherein. In some examples, aspects of the operations of 1215 may beperformed by a timing manager as described with reference to FIGS. 7through 10.

FIG. 13 shows a flowchart illustrating a method 1300 that supportswireless communication system enhancements for transparent and boundaryclocks in accordance with aspects of the present disclosure. Theoperations of method 1300 may be implemented by a UE 115, a UPF, orassociated components as described herein. For example, the operationsof method 1300 may be performed by a communications manager as describedwith reference to FIGS. 2 and 4-10. In some examples, a UE or UPF mayexecute a set of instructions to control the functional elements of theUE or UPF to perform the functions described below. Additionally oralternatively, a UE or UPF may perform aspects of the functionsdescribed below using special-purpose hardware.

At 1305, the UE or UPF may receive a frame including a PTP message. Theoperations of 1305 may be performed according to the methods describedherein. In some examples, aspects of the operations of 1305 may beperformed by a receiver as described with reference to FIGS. 7 through10.

At 1310, the UE or UPF may transmit, to a second node of the wirelesscommunication network, a session connectivity message associated with aPDU session for conveying the frame, the session connectivity messageincluding an indicator that the PDU session supports PTP messages. Theoperations of 1310 may be performed according to the methods describedherein. In some examples, aspects of the operations of 1310 may beperformed by a transmitter as described with reference to FIGS. 7through 10.

At 1315, the UE or UPF may send, to the second node, a PDU including thePTP message. The operations of 1315 may be performed according to themethods described herein. In some examples, aspects of the operations of1315 may be performed by a transmitter as described with reference toFIGS. 7 through 10.

FIG. 14 shows a flowchart illustrating a method 1400 that supportswireless communication system enhancements for transparent and boundaryclocks in accordance with aspects of the present disclosure. Theoperations of method 1400 may be implemented by a UE 115, a UPF, orassociated components as described herein. For example, the operationsof method 1400 may be performed by a communications manager as describedwith reference to FIGS. 2 and 4-10. In some examples, a UE or UPF mayexecute a set of instructions to control the functional elements of theUE or UPF to perform the functions described below. Additionally oralternatively, a UE or UPF may perform aspects of the functionsdescribed below using special-purpose hardware.

At 1405, the UE or UPF may receive, from a second node of the wirelesscommunication network, a session connectivity message associated with aPDU session, the session connectivity message including an indicatorthat the PDU session supports PTP messages. The operations of 1405 maybe performed according to the methods described herein. In someexamples, aspects of the operations of 1405 may be performed by areceiver as described with reference to FIGS. 7 through 10.

At 1410, the UE or UPF may monitor one or more PDUs received from thesecond node for PTP messages based on the indicator that the PDU sessionsupports PTP messages. The operations of 1410 may be performed accordingto the methods described herein. In some examples, aspects of theoperations of 1410 may be performed by a PDU manager as described withreference to FIGS. 7 through 10.

At 1415, the UE or UPF may identify a PTP message in a PDU of the one ormore PDUs based on the monitoring. The operations of 1415 may beperformed according to the methods described herein. In some examples,aspects of the operations of 1415 may be performed by a PDU manager asdescribed with reference to FIGS. 7 through 10.

FIG. 15 shows a flowchart illustrating a method 1500 that supportswireless communication system enhancements for transparent and boundaryclocks in accordance with aspects of the present disclosure. Theoperations of method 1500 may be implemented by a UE 115, a UPF, orassociated components as described herein. For example, the operationsof method 1500 may be performed by a communications manager as describedwith reference to FIGS. 2 and 4-10. In some examples, a UE or UPF mayexecute a set of instructions to control the functional elements of theUE or UPF to perform the functions described below. Additionally oralternatively, a UE or UPF may perform aspects of the functionsdescribed below using special-purpose hardware.

At 1505, the UE or UPF may receive, at a first node of a wirelesscommunication network, a first ethernet frame including a first PTPmessage. The operations of 1505 may be performed according to themethods described herein. In some examples, aspects of the operations of1505 may be performed by a receiver as described with reference to FIGS.7 through 10.

At 1510, the UE or UPF may determine an ingress time for the first PTPmessage received at the first node. The operations of 1510 may beperformed according to the methods described herein. In some examples,aspects of the operations of 1510 may be performed by a timing manageras described with reference to FIGS. 7 through 10.

At 1515, the UE or UPF may receive a second ethernet frame including asecond PTP message associated with the first PTP message. The secondethernet frame may be a Follow_Up PTP message associated with a Sync PTPmessage. The operations of 1515 may be performed according to themethods described herein. In some examples, aspects of the operations of1515 may be performed by a receiver as described with reference to FIGS.7 through 10.

At 1520, the UE or UPF may generate a PDU for transmission to a secondnode of the wireless communication network based on the second ethernetframe, the PDU including a value corresponding to the ingress time forthe first PTP message. The operations of 1520 may be performed accordingto the methods described herein. In some examples, aspects of theoperations of 1520 may be performed by a PDU manager as described withreference to FIGS. 7 through 10.

At 1525, the UE or UPF may transmit the PDU to the second node. Theoperations of 1525 may be performed according to the methods describedherein. In some examples, aspects of the operations of 1525 may beperformed by a transmitter as described with reference to FIGS. 7through 10.

FIG. 16 shows a flowchart illustrating a method 1600 that supportswireless communication system enhancements for transparent and boundaryclocks in accordance with aspects of the present disclosure. Theoperations of method 1600 may be implemented by a UE 115, a UPF, orassociated components as described herein. For example, the operationsof method 1600 may be performed by a communications manager as describedwith reference to FIGS. 2 and 4-10. In some examples, a UE or UPF mayexecute a set of instructions to control the functional elements of theUE or UPF to perform the functions described below. Additionally oralternatively, a UE or UPF may perform aspects of the functionsdescribed below using special-purpose hardware.

At 1605, the UE or UPF may receive, from a second node of the wirelesscommunication network, a PDU associated with first and second ethernetframes received at the second node, the first ethernet frame including afirst PTP message, and the second ethernet frame including a second PTPmessage. The operations of 1605 may be performed according to themethods described herein. In some examples, aspects of the operations of1605 may be performed by a receiver as described with reference to FIGS.7 through 10.

At 1610, the UE or UPF may determine an ingress time for the first PTPmessage received at the second node based on the PDU. The operations of1610 may be performed according to the methods described herein. In someexamples, aspects of the operations of 1610 may be performed by a timingmanager as described with reference to FIGS. 7 through 10.

At 1615, the UE or UPF may determine an adjustment for a timingparameter of the second PTP message based on the ingress time. Theoperations of 1615 may be performed according to the methods describedherein. In some examples, aspects of the operations of 1615 may beperformed by a timing manager as described with reference to FIGS. 7through 10.

In some examples, method 1600 may further include using the ingresstimestamp as an ingress time for a residence time computation usingadditional information such as a reception time at a wirelesscommunication system egress point. In some examples, method 1600 mayinclude optionally send an ethernet frame associated with the firstethernet PDU outside wireless communication system after settingoriginTimeStamp in the PTP message associated with the PDU based onpreciseOriginTimeStamp in the second PTP message (e.g., Follow_Upmessage) and the residence time computation. Some examples may includesending an ethernet frame associated with the second ethernet PDUoutside wireless communication system after either removing any appendedingress timestamp from the ethernet frame if the ingress timestamp isappended to the ethernet frame or setting a field in the second PTPmessage containing ingress timestamp to a configured value (e.g., zero)if a field in the PTP message is used to send ingress timestamp. Method16 may also send an ethernet frame after adjusting (e.g., adding orsubtracting) a correction field in the second PTP message based on theresidence time computation or adjusting (e.g., adding or subtracting) apreciseOriginTimeStamp field in the second PTP message based on theresidence time computation.

FIG. 17 shows a flowchart illustrating a method 1700 that supportswireless communication system enhancements for transparent and boundaryclocks in accordance with aspects of the present disclosure. Theoperations of method 1700 may be implemented by a UE 115, a UPF, orassociated components as described herein. For example, the operationsof method 1700 may be performed by a communications manager as describedwith reference to FIGS. 2 and 4-10. In some examples, a UE or UPF mayexecute a set of instructions to control the functional elements of theUE or UPF to perform the functions described below. Additionally oralternatively, a UE or UPF may perform aspects of the functionsdescribed below using special-purpose hardware. In some examples, awireless communication system acting as a peer-to-peer transparent clockmay need to correct for a delay of an incoming link associated with aPTP message.

At 1705, the UE or UPF may receive, from a time sensitive network, anethernet frame including a PTP message. The operations of 1705 may beperformed according to the methods described herein. In some examples,aspects of the operations of 1705 may be performed by a receiver asdescribed with reference to FIGS. 7 through 10.

At 1710, the UE or UPF may determine a link delay time for the PTPmessage between transmission from the time sensitive network andreception by the first node. In some examples, the link delay time canbe determined using a peer delay mechanism. The operations of 1710 maybe performed according to the methods described herein. In someexamples, aspects of the operations of 1710 may be performed by a linkdelay manager as described with reference to FIGS. 7 through 10.

At 1715, the UE or UPF may generate a PDU for transmission to a secondnode of the wireless communication network based on adjusting a field ofthe PTP message according to a link delay. The operations of 1715 may beperformed according to the methods described herein. In some examples,aspects of the operations of 1715 may be performed by a PDU manager asdescribed with reference to FIGS. 7 through 10.

At 1720, the UE or UPF may transmit the PDU to the second node. Theoperations of 1720 may be performed according to the methods describedherein. In some examples, aspects of the operations of 1720 may beperformed by a transmitter as described with reference to FIGS. 7through 10.

FIG. 18 shows a flowchart illustrating a method 1800 that supportswireless communication system enhancements for transparent and boundaryclocks in accordance with aspects of the present disclosure. Theoperations of method 1800 may be implemented by a UE 115, a UPF, orassociated components as described herein. For example, the operationsof method 1800 may be performed by a communications manager as describedwith reference to FIGS. 2 and 4-10. In some examples, a UE or UPF mayexecute a set of instructions to control the functional elements of theUE or UPF to perform the functions described below. Additionally oralternatively, a UE or UPF may perform aspects of the functionsdescribed below using special-purpose hardware.

At 1805, the UE or UPF may receive a PTP message. The operations of 1805may be performed according to the methods described herein. In someexamples, aspects of the operations of 1805 may be performed by areceiver as described with reference to FIGS. 7 through 10.

At 1810, the UE or UPF may identify one or more relevant timing domainsfor the wireless communication network based on the PTP message. Theoperations of 1810 may be performed according to the methods describedherein. In some examples, aspects of the operations of 1810 may beperformed by a timing manager as described with reference to FIGS. 7through 10.

At 1815, the UE or UPF may maintain a boundary clock for each of the oneor more timing domains. The operations of 1815 may be performedaccording to the methods described herein. In some examples, aspects ofthe operations of 1815 may be performed by a timing manager as describedwith reference to FIGS. 7 through 10.

FIG. 19 shows a flowchart illustrating a method 1900 that supportswireless communication system enhancements for transparent and boundaryclocks in accordance with aspects of the present disclosure. Theoperations of method 1900 may be implemented by a UE 115, a UPF, orassociated components as described herein. For example, the operationsof method 1900 may be performed by a communications manager as describedwith reference to FIGS. 2 and 4-10. In some examples, a UE or UPF mayexecute a set of instructions to control the functional elements of theUE or UPF to perform the functions described below. Additionally oralternatively, a UE or UPF may perform aspects of the functionsdescribed below using special-purpose hardware.

At 1905, the UE or UPF may receive, from one or more UEs served by thefirst node, an indicator of one or more timing domains to be supportedby the one or more UEs. The operations of 1905 may be performedaccording to the methods described herein. In some examples, aspects ofthe operations of 1905 may be performed by a receiver as described withreference to FIGS. 7 through 10.

At 1910, the UE or UPF may transmit, for each timing domain of the oneor more timing domains, an identifier of the timing domain and timinginformation associated with the timing domain. The operations of 1910may be performed according to the methods described herein. In someexamples, aspects of the operations of 1910 may be performed by atransmitter as described with reference to FIGS. 7 through 10.

In some examples, the UE or UPF may identify relevant timing domains bytracking timing domain information in received PTP messages andoptionally tracking corresponding VLAN tags associated with ethernetpackets containing the PTP messages. The UE or UPF may save the domaininformation in a received PTP message contained in domainNumber field inheader of the PTP message. Specific examples for timing domaininformation in PTP messages may include that the UE may save domaininformation in a Pdelay_req message contained in domainNumber field inheader of the Pdelay_req message or that UE may save domain informationin a Announce message contained in domainNumber field in header of theAnnounce message. A timing domain may be removed from a list of relevanttiming domains if the associated timing domain is not part of any PTPmessages for a duration greater than TimingDomain_TimeoutDuration.

In some examples, the UE or UPF may act as a boundary clock for each ofa subset of identified timing domains. In other examples, the UE or UPFmay act as a boundary clock for each of a subset of combination ofidentified timing domains and corresponding VLAN tags. Thisfunctionality can be performed at the UE or at an adaptor/translatorconnected to the UE.

With multiple timing domains, wireless communication system may act as aboundary clock for each timing domain and RAN broadcasts timinginformation (e.g., an offset with respect to a 5G clock known to the RANand the UE) associated with each such timing domain. Timing domains mayalso be confined by VLAN tags used for associated ethernet packets andframes. For example, two different timing domains may use same timingdomain identifier in PTP messages (e.g., in domainNumber field) and butdifferent VLAN tags in associated ethernet packet/frames.

The RAN may indicate timing domain information for each broadcastedtiming domain including associated VLAN information because, for eachtiming domain for which the RAN sends timing information, the RANadditionally indicates (e.g., via a SIB or a unicast RRC message) atiming domain information including a timing domain identifier andoptional VLAN information (e.g., VLAN Identifier or VID) based on VLANtags associated with PTP messages received by RAN. The UE tracks asubset of timing information sent by the RAN and the UE saves the timingdomain information associated with each of the subset of timinginformation sent by RAN and optionally runs PTP master clock based onthe timing information and associated timing domain information. Forinstance, the PTP master clock uses same domainNumber in sent PTPmessages or the PTP master clock uses same VLAN information (e.g., VID)in sent ethernet packets with PTP messages.

FIG. 20 shows a flowchart illustrating a method 2000 that supportswireless communication system enhancements for transparent and boundaryclocks in accordance with aspects of the present disclosure. Theoperations of method 2000 may be implemented by a UE 115, a UPF, orassociated components as described herein. For example, the operationsof method 2000 may be performed by a communications manager as describedwith reference to FIGS. 2 and 4-10. In some examples, a UE or UPF mayexecute a set of instructions to control the functional elements of theUE or UPF to perform the functions described below. Additionally oralternatively, a UE or UPF may perform aspects of the functionsdescribed below using special-purpose hardware.

At 2005, the UE or UPF may receive, from a second node of the wirelesscommunication network, an indicator of one or more timing domainssupported by a third node of the wireless communication network. In someexamples, the second node and the third node may be a same node. Theoperations of 2005 may be performed according to the methods describedherein. In some examples, aspects of the operations of 2005 may beperformed by a receiver as described with reference to FIGS. 7 through10.

At 2010, the UE or UPF may process one or more PTP messages associatedwith a PDU session according to the one or more timing domains supportedby the third node. For example, the first node may distribute PTPmessages according to supported timing domains. That is, the first nodemay receive indications of supported timing domains from multiple nodes,and distribute received PTP messages according to the indications ofsupported timing domains (e.g., distributing PTP message associated witha given timing domain to nodes that support the given timing domain).The operations of 2010 may be performed according to the methodsdescribed herein. In some examples, aspects of the operations of 2010may be performed by a receiver as described with reference to FIGS. 7through 10.

FIG. 21 shows a flowchart illustrating a method 2100 that supportswireless communication system enhancements for transparent and boundaryclocks in accordance with aspects of the present disclosure. Theoperations of method 2100 may be implemented by a UE 115, a UPF, orassociated components as described herein. For example, the operationsof method 2100 may be performed by a communications manager as describedwith reference to FIGS. 2 and 4-10. In some examples, a UE or UPF mayexecute a set of instructions to control the functional elements of theUE or UPF to perform the functions described below. Additionally oralternatively, a UE or UPF may perform aspects of the functionsdescribed below using special-purpose hardware.

At 2105, the UE or UPF may receive a PTP message. The operations of 2105may be performed according to the methods described herein. In someexamples, aspects of the operations of 2105 may be performed by areceiver as described with reference to FIGS. 7 through 10.

At 2110, the UE or UPF may identify one or more timing domains to besupported by the first node based at least in part on the PTP message.The operations of 2110 may be performed according to the methodsdescribed herein. In some examples, aspects of the operations of 2110may be performed by a receiver as described with reference to FIGS. 7through 10.

At 2115, the UE or UPF may send, to a second node of the wirelesscommunication network, an indicator of the one or more timing domains tobe supported by the first node. The operations of 2115 may be performedaccording to the methods described herein. In some examples, aspects ofthe operations of 2115 may be performed by a receiver as described withreference to FIGS. 7 through 10.

In some examples, method 1200 may further include identifying a networktag in a frame associated with the PTP message, wherein identifying theone or more timing domains to be supported by the first node is furtherbased at least in part on the network tag. In another example, method1200 further includes removing a timing domain from the one or moretiming domains based at least in part on a duration between PTP messagesassociated with the timing domain satisfying a threshold. In anotherexample, method 1200 includes sending, to the second node, an updatedindicator of the one or more timing domains excluding the timing domain.

FIG. 22 shows a flowchart illustrating a method 2200 that supportswireless communication system enhancements for transparent and boundaryclocks in accordance with aspects of the present disclosure. Theoperations of method 2200 may be implemented by a UE 115, a UPF, orassociated components as described herein. For example, the operationsof method 2200 may be performed by a communications manager as describedwith reference to FIGS. 2 and 4-10. In some examples, a UE or UPF mayexecute a set of instructions to control the functional elements of theUE or UPF to perform the functions described below. Additionally oralternatively, a UE or UPF may perform aspects of the functionsdescribed below using special-purpose hardware.

At 2205, the UE or UPF may identify, for a PDU session with a secondnode of the wireless communication network, that the PDU sessionsupports PTP messages. The operations of 2205 may be performed accordingto the methods described herein. In some examples, aspects of theoperations of 2205 may be performed by a receiver as described withreference to FIGS. 7 through 10.

At 2210, the UE or UPF may send, to the second node of the wirelesscommunication network, an indicator of the support of PTP messages forthe PDU session. In some examples, the indicator is included in aninformation element of a PDU. The operations of 2210 may be performedaccording to the methods described herein. In some examples, aspects ofthe operations of 2205 may be performed by a receiver as described withreference to FIGS. 7 through 10.

FIG. 23 shows a flowchart illustrating a method 2300 that supportswireless communication system enhancements for transparent and boundaryclocks in accordance with aspects of the present disclosure. Theoperations of method 2300 may be implemented by a UE 115 or base station105 or its components as described herein. For example, the operationsof method 2300 may be performed by a communications manager as describedwith reference to FIGS. 2 and 4-10. In some examples, a UE or UPF mayexecute a set of instructions to control the functional elements of theUE or UPF to perform the functions described below. Additionally oralternatively, a UE or UPF may perform aspects of the functionsdescribed below using special-purpose hardware.

At 2305, the UE or UPF may identify, for a PDU session with a secondnode of the wireless communication network, that the PDU session carriesPTP messages. The operations of 2305 may be performed according to themethods described herein. In some examples, aspects of the operations of2305 may be performed by a receiver as described with reference to FIGS.7 through 10.

At 2310, the UE or UPF may send, to the second node of the wirelesscommunication network, an indicator of a capability of the first nodefor filtering Sync messages of the PTP messages. In some examples, theindicator is included in an information element of a PDU. Theinformation element may be a new field associated with the PDU. Theoperations of 2310 may be performed according to the methods describedherein. In some examples, aspects of the operations of 2310 may beperformed by a receiver as described with reference to FIGS. 7 through10.

At 2315, the UE or UPF may filter one or more Sync messages associatedwith the PDU session received at the first node. The operations of 2315may be performed according to the methods described herein. In someexamples, aspects of the operations of 2315 may be performed by areceiver as described with reference to FIGS. 7 through 10.

FIG. 24 shows a flowchart illustrating a method 2400 that supportswireless communication system enhancements for transparent and boundaryclocks in accordance with aspects of the present disclosure. Theoperations of method 2400 may be implemented by a UE 115 or base station105 or its components as described herein. For example, the operationsof method 2400 may be performed by a communications manager as describedwith reference to FIGS. 2 and 4-10. In some examples, a UE or UPF mayexecute a set of instructions to control the functional elements of theUE or UPF to perform the functions described below. Additionally oralternatively, a UE or UPF may perform aspects of the functionsdescribed below using special-purpose hardware.

At 2405, the UE or UPF may establish a PDU session with a second node ofthe wireless communication network, the PDU session associated with PTPmessages. The operations of 2405 may be performed according to themethods described herein. In some examples, aspects of the operations of2405 may be performed by a receiver as described with reference to FIGS.7 through 10.

At 2410, the UE or UPF may receive, from the second node of the wirelesscommunication network, an indicator of a capability of the second nodefor filtering Sync messages of the PTP messages. In some examples, theindicator is included in an information element of a PDU. Theinformation element may be a new field associated with the PDU. Theoperations of 2410 may be performed according to the methods describedherein. In some examples, aspects of the operations of 2410 may beperformed by a receiver as described with reference to FIGS. 7 through10.

At 2415, the UE or UPF may process one or more PTP messages from thesecond node based at least in part on the indicator. The operations of2415 may be performed according to the methods described herein. In someexamples, aspects of the operations of 2415 may be performed by areceiver as described with reference to FIGS. 7 through 10.

It should be noted that the methods described herein describe possibleimplementations, and that the operations and the steps may be rearrangedor otherwise modified and that other implementations are possible.Further, aspects from two or more of the methods may be combined.

Techniques described herein may be used for various wirelesscommunication networks such as code division multiple access (CDMA),time division multiple access (TDMA), frequency division multiple access(FDMA), orthogonal frequency division multiple access (OFDMA), singlecarrier frequency division multiple access (SC-FDMA), and other systems.A CDMA system may implement a radio technology such as CDMA2000,Universal Terrestrial Radio Access (UTRA), etc. CDMA2000 covers IS-2000,IS-95, and IS-856 standards. IS-2000 Releases may be commonly referredto as CDMA2000 1×, 1×, etc. IS-856 (TIA-856) is commonly referred to asCDMA2000 1×EV-DO, High Rate Packet Data (HRPD), etc. UTRA includesWideband CDMA (WCDMA) and other variants of CDMA. A TDMA system mayimplement a radio technology such as Global System for MobileCommunications (GSM).

An OFDMA system may implement a radio technology such as Ultra MobileBroadband (UMB), Evolved UTRA (E-UTRA), Institute of Electrical andElectronics Engineers (IEEE) 802.11 (Wi-Fi), IEEE 802.16 (WiMAX), IEEE802.20, Flash-OFDM, etc. UTRA and E-UTRA are part of Universal MobileTelecommunications System (UMTS). LTE, LTE-A, and LTE-A Pro are releasesof UMTS that use E-UTRA. UTRA, E-UTRA, UMTS, LTE, LTE-A, LTE-A Pro, NR,and GSM are described in documents from the organization named “3rdGeneration Partnership Project” (3GPP). CDMA2000 and UMB are describedin documents from an organization named “3rd Generation PartnershipProject 2” (3GPP2). The techniques described herein may be used for thesystems and radio technologies mentioned herein as well as other systemsand radio technologies. While aspects of an LTE, LTE-A, LTE-A Pro, or NRsystem may be described for purposes of example, and LTE, LTE-A, LTE-APro, or NR terminology may be used in much of the description, thetechniques described herein are applicable beyond LTE, LTE-A, LTE-A Pro,or NR applications.

A macro cell generally covers a relatively large geographic area (e.g.,several kilometers in radius) and may allow unrestricted access by UEswith service subscriptions with the network provider. A small cell maybe associated with a lower-powered base station, as compared with amacro cell, and a small cell may operate in the same or different (e.g.,licensed, unlicensed, etc.) frequency bands as macro cells. Small cellsmay include pico cells, femto cells, and micro cells according tovarious examples. A pico cell, for example, may cover a small geographicarea and may allow unrestricted access by UEs with service subscriptionswith the network provider. A femto cell may also cover a smallgeographic area (e.g., a home) and may provide restricted access by UEshaving an association with the femto cell (e.g., UEs in a closedsubscriber group (CSG), UEs for users in the home, and the like). An eNBfor a macro cell may be referred to as a macro eNB. An eNB for a smallcell may be referred to as a small cell eNB, a pico eNB, a femto eNB, ora home eNB. An eNB may support one or multiple (e.g., two, three, four,and the like) cells, and may also support communications using one ormultiple component carriers.

The wireless communication networks described herein may supportsynchronous or asynchronous operation. For synchronous operation, thebase stations may have similar frame timing, and transmissions fromdifferent base stations may be approximately aligned in time. Forasynchronous operation, the base stations may have different frametiming, and transmissions from different base stations may not bealigned in time. The techniques described herein may be used for eithersynchronous or asynchronous operations.

Information and signals described herein may be represented using any ofa variety of different technologies and techniques. For example, data,instructions, commands, information, signals, bits, symbols, and chipsthat may be referenced throughout the description may be represented byvoltages, currents, electromagnetic waves, magnetic fields or particles,optical fields or particles, or any combination thereof.

The various illustrative blocks and modules described in connection withthe disclosure herein may be implemented or performed with ageneral-purpose processor, a DSP, an ASIC, an FPGA, or otherprogrammable logic device, discrete gate or transistor logic, discretehardware components, or any combination thereof designed to perform thefunctions described herein. A general-purpose processor may be amicroprocessor, but in the alternative, the processor may be anyconventional processor, controller, microcontroller, or state machine. Aprocessor may also be implemented as a combination of computing devices(e.g., a combination of a DSP and a microprocessor, multiplemicroprocessors, one or more microprocessors in conjunction with a DSPcore, or any other such configuration).

The functions described herein may be implemented in hardware, softwareexecuted by a processor, firmware, or any combination thereof. Ifimplemented in software executed by a processor, the functions may bestored on or transmitted over as one or more instructions or code on acomputer-readable medium. Other examples and implementations are withinthe scope of the disclosure and appended claims. For example, due to thenature of software, functions described herein can be implemented usingsoftware executed by a processor, hardware, firmware, hardwiring, orcombinations of any of these. Features implementing functions may alsobe physically located at various positions, including being distributedsuch that portions of functions are implemented at different physicallocations.

Computer-readable media includes both non-transitory computer storagemedia and communication media including any medium that facilitatestransfer of a computer program from one place to another. Anon-transitory storage medium may be any available medium that can beaccessed by a general purpose or special purpose computer. By way ofexample, and not limitation, non-transitory computer-readable media mayinclude random-access memory (RAM), read-only memory (ROM), electricallyerasable programmable ROM (EEPROM), flash memory, compact disk (CD) ROMor other optical disk storage, magnetic disk storage or other magneticstorage devices, or any other non-transitory medium that can be used tocarry or store desired program code means in the form of instructions ordata structures and that can be accessed by a general-purpose orspecial-purpose computer, or a general-purpose or special-purposeprocessor. Also, any connection is properly termed a computer-readablemedium. For example, if the software is transmitted from a website,server, or other remote source using a coaxial cable, fiber optic cable,twisted pair, digital subscriber line (DSL), or wireless technologiessuch as infrared, radio, and microwave, then the coaxial cable, fiberoptic cable, twisted pair, DSL, or wireless technologies such asinfrared, radio, and microwave are included in the definition of medium.Disk and disc, as used herein, include CD, laser disc, optical disc,digital versatile disc (DVD), floppy disk and Blu-ray disc where disksusually reproduce data magnetically, while discs reproduce dataoptically with lasers. Combinations of the above are also includedwithin the scope of computer-readable media.

As used herein, including in the claims, “or” as used in a list of items(e.g., a list of items prefaced by a phrase such as “at least one of” or“one or more of”) indicates an inclusive list such that, for example, alist of at least one of A, B, or C means A or B or C or AB or AC or BCor ABC (i.e., A and B and C). Also, as used herein, the phrase “basedon” shall not be construed as a reference to a closed set of conditions.For example, an exemplary step that is described as “based on conditionA” may be based on both a condition A and a condition B withoutdeparting from the scope of the present disclosure. For example, as usedherein, the phrase “based on” shall be construed in the same manner asthe phrase “based at least in part on.”

In the appended figures, similar components or features may have thesame reference label. Further, various components of the same type maybe distinguished by following the reference label by a dash and a secondlabel that distinguishes among the similar components. If just the firstreference label is used in the specification, the description isapplicable to any one of the similar components having the same firstreference label irrespective of the second reference label, or othersubsequent reference label.

The description set forth herein, in connection with the appendeddrawings, describes example configurations and does not represent allthe examples that may be implemented or that are within the scope of theclaims. The term “exemplary” used herein means “serving as an example,instance, or illustration,” and not “preferred” or “advantageous overother examples.” The detailed description includes specific details forthe purpose of providing an understanding of the described techniques.These techniques, however, may be practiced without these specificdetails. In some instances, well-known structures and devices are shownin block diagram form in order to avoid obscuring the concepts of thedescribed examples.

The description herein is provided to enable a person skilled in the artto make or use the disclosure. Various modifications to the disclosurewill be readily apparent to those skilled in the art, and the genericprinciples defined herein may be applied to other variations withoutdeparting from the scope of the disclosure. Thus, the disclosure is notlimited to the examples and designs described herein but is to beaccorded the broadest scope consistent with the principles and novelfeatures disclosed herein.

What is claimed is:
 1. A method at a first node of a wirelesscommunication network, comprising: receiving, at a first node of awireless communication network, a first ethernet frame comprising afirst precision time protocol (PTP) message; determining an ingress timefor the first PTP message received at the first node; receiving a secondethernet frame comprising a second PTP message associated with the firstPTP message; generating a packet data unit (PDU) for transmission to asecond node of the wireless communication network based at least in parton the second ethernet frame, the PDU comprising a value correspondingto the ingress time for the first PTP message; and transmitting the PDUto the second node.
 2. The method of claim 1, wherein generating the PDUfor transmission comprises: appending the value corresponding to theingress time for the first PTP message to the second ethernet frame inthe PDU.
 3. The method of claim 1, wherein generating the PDU fortransmission further comprises: modifying the second ethernet frame byoverwriting a timestamp field of the second PTP message with the valuecorresponding to the ingress time.
 4. The method of claim 1, whereingenerating the PDU for transmission further comprises: modifying thesecond ethernet frame by overwriting a field of a header of the secondPTP message with the value corresponding to the ingress time.
 5. Themethod of claim 1, wherein generating the PDU further comprises:modifying the second ethernet frame by overwriting a type linked value(TLV) of the second PTP message with the value corresponding to theingress time.
 6. The method of claim 1, wherein generating the PDUfurther comprises: adjusting the ingress time for the PTP message toaccount for a link delay associated with the PTP message.
 7. The methodof claim 1, further comprising: providing an indication to the secondnode that an associated PDU session may carry PTP messages.
 8. Themethod of claim 1, further comprising: suppressing transmission of thefirst PTP message to the second node.
 9. The method of claim 1, furthercomprising: receiving an indicator of support of the second node forsuppressing transmission of the first PTP message to the second node.10. The method of claim 9, wherein the indicator is associated with aPDU session associated with the first and second PTP messages.
 11. Themethod of claim 9, wherein the indicator is associated with the PDU. 12.The method of claim 1, further comprising: signaling that the first nodecan filter Sync messages associated with the PTP message.
 13. A methodat a first node of a wireless communication network, comprising:receiving, from a second node of the wireless communication network, apacket data unit (PDU) associated with first and second ethernet framesreceived at the second node, the first ethernet frame comprising a firstprecision time protocol (PTP) message, and the second ethernet framecomprising a second PTP message; determining an ingress time for thefirst PTP message received at the second node based at least in part onthe PDU; and determining an adjustment for a timing parameter of thesecond PTP message based at least in part on the ingress time.
 14. Themethod of claim 13, further comprising: determining an egress time for athird ethernet frame comprising a modified version of the first PTPmessage; and determining a residence time correction for the modifiedversion of the first PTP message time by subtracting the ingress timefrom the egress time.
 15. The method of claim 14, further comprising:transmitting the third ethernet frame comprising a modified version ofthe second PTP message that identifies an adjustment to a time sensitivenetwork, wherein a correction field of the modified version of thesecond PTP message is modified using the residence time correction. 16.The method of claim 13, wherein determining the ingress time comprisesone of identifying a value corresponding to the ingress time for thefirst PTP message from an overwritten field of the second PTP message oridentifying one or more octets corresponding to the ingress time in thePDU.
 17. The method of claim 13, further comprising: receiving anindication that a PDU session associated with the first and second PTPmessages supports PTP messages.
 18. The method of claim 13, whereindetermining the adjustment further comprises: adjusting the modifiedversion of the second PTP message by setting the overwritten field inthe PTP message to a configured value.
 19. An apparatus, comprising: aprocessor; memory in electronic communication with the processor; andinstructions stored in the memory and executable by the processor tocause the apparatus to: receive, at a first node of a wirelesscommunication network, a first ethernet frame comprising a firstprecision time protocol (PTP) message; determine an ingress time for thefirst PTP message received at the first node; receive a second ethernetframe comprising a second PTP message associated with the first PTPmessage; generate a packet data unit (PDU) for transmission to a secondnode of the wireless communication network based at least in part on thesecond ethernet frame, the PDU comprising a value corresponding to theingress time for the first PTP message; and transmit the PDU to thesecond node.
 20. The apparatus of claim 19, wherein the instructions togenerate the PDU for transmission are executable by the processor tocause the apparatus to: append the value corresponding to the ingresstime for the first PTP message to the second ethernet frame in the PDU.21. The apparatus of claim 19, wherein the instructions to generate thePDU further are executable by the processor to cause the apparatus to:adjust the ingress time for the PTP message to account for a link delayassociated with the PTP message.
 22. The apparatus of claim 19, whereinthe instructions are further executable by the processor to cause theapparatus to: provide an indication to the second node that anassociated PDU session may carry PTP messages.
 23. The apparatus ofclaim 19, wherein the instructions are further executable by theprocessor to cause the apparatus to: suppress transmission of the firstPTP message to the second node.
 24. The apparatus of claim 19, whereinthe instructions are further executable by the processor to cause theapparatus to: receive an indicator of support of the second node forsuppressing transmission of the first PTP message to the second node.25. The apparatus of claim 24, wherein the indicator is associated withone of a PDU session associated with the first and second PTP messagesor the PDU.
 26. The apparatus of claim 19, wherein the instructions arefurther executable by the processor to cause the apparatus to: signalthat the first node can filter Sync messages associated with the PTPmessage.
 27. An apparatus, comprising: a processor; memory in electroniccommunication with the processor; and instructions stored in the memoryand executable by the processor to cause the apparatus to: receive, froma second node of the wireless communication network, a packet data unit(PDU) associated with first and second ethernet frames received at thesecond node, the first ethernet frame comprising a first precision timeprotocol (PTP) message, and the second ethernet frame comprising asecond PTP message; determine an ingress time for the first PTP messagereceived at the second node based at least in part on the PDU; anddetermine an adjustment for a timing parameter of the second PTP messagebased at least in part on the ingress time.
 28. The apparatus of claim27, wherein the instructions are further executable by the processor tocause the apparatus to: determine an egress time for a third ethernetframe comprising a modified version of the first PTP message; anddetermine a residence time correction for the modified version of thefirst PTP message time by subtracting the ingress time from the egresstime.
 29. The apparatus of claim 28, wherein the instructions arefurther executable by the processor to cause the apparatus to: transmitthe third ethernet frame comprising a modified version of the second PTPmessage that identifies an adjustment to a time sensitive network,wherein a correction field of the modified version of the second PTPmessage is modified using the residence time correction.
 30. Theapparatus of claim 28, wherein the instructions are further executableby the processor to cause the apparatus to: receive an indication that aPDU session associated with the first and second PTP messages supportsPTP messages.